15 files changed, 7 insertions, 611 deletions

diff --git a/src/WixToolset.BootstrapperCore.Native/inc/BootstrapperApplication.h b/src/WixToolset.BootstrapperCore.Native/inc/BootstrapperApplication.h
index 80b23686..c0baa958 100644
--- a/src/WixToolset.BootstrapperCore.Native/inc/BootstrapperApplication.h
+++ b/src/WixToolset.BootstrapperCore.Native/inc/BootstrapperApplication.h
@@ -92,15 +92,12 @@ enum BOOTSTRAPPER_APPLICATION_MESSAGE
     BOOTSTRAPPER_APPLICATION_MESSAGE_ONDETECTUPDATECOMPLETE,
     BOOTSTRAPPER_APPLICATION_MESSAGE_ONDETECTRELATEDBUNDLE,
     BOOTSTRAPPER_APPLICATION_MESSAGE_ONDETECTPACKAGEBEGIN,
-    BOOTSTRAPPER_APPLICATION_MESSAGE_ONDETECTCOMPATIBLEMSIPACKAGE,
     BOOTSTRAPPER_APPLICATION_MESSAGE_ONDETECTRELATEDMSIPACKAGE,
     BOOTSTRAPPER_APPLICATION_MESSAGE_ONDETECTTARGETMSIPACKAGE,
     BOOTSTRAPPER_APPLICATION_MESSAGE_ONDETECTMSIFEATURE,
     BOOTSTRAPPER_APPLICATION_MESSAGE_ONDETECTPACKAGECOMPLETE,
     BOOTSTRAPPER_APPLICATION_MESSAGE_ONPLANRELATEDBUNDLE,
     BOOTSTRAPPER_APPLICATION_MESSAGE_ONPLANPACKAGEBEGIN,
-    BOOTSTRAPPER_APPLICATION_MESSAGE_ONPLANCOMPATIBLEMSIPACKAGEBEGIN,
-    BOOTSTRAPPER_APPLICATION_MESSAGE_ONPLANCOMPATIBLEMSIPACKAGECOMPLETE,
     BOOTSTRAPPER_APPLICATION_MESSAGE_ONPLANTARGETMSIPACKAGE,
     BOOTSTRAPPER_APPLICATION_MESSAGE_ONPLANMSIFEATURE,
     BOOTSTRAPPER_APPLICATION_MESSAGE_ONPLANPACKAGECOMPLETE,
@@ -469,20 +466,6 @@ struct BA_ONDETECTBEGIN_RESULTS
     BOOL fCancel;
 };
 
-struct BA_ONDETECTCOMPATIBLEMSIPACKAGE_ARGS
-{
-    DWORD cbSize;
-    LPCWSTR wzPackageId;
-    LPCWSTR wzCompatiblePackageId;
-    LPCWSTR wzCompatiblePackageVersion;
-};
-
-struct BA_ONDETECTCOMPATIBLEMSIPACKAGE_RESULTS
-{
-    DWORD cbSize;
-    BOOL fCancel;
-};
-
 struct BA_ONDETECTCOMPLETE_ARGS
 {
     DWORD cbSize;
@@ -855,39 +838,6 @@ struct BA_ONPLANBEGIN_RESULTS
     BOOL fCancel;
 };
 
-struct BA_ONPLANCOMPATIBLEMSIPACKAGEBEGIN_ARGS
-{
-    DWORD cbSize;
-    LPCWSTR wzPackageId;
-    LPCWSTR wzCompatiblePackageId;
-    LPCWSTR wzCompatiblePackageVersion;
-    BOOTSTRAPPER_REQUEST_STATE recommendedState;
-};
-
-struct BA_ONPLANCOMPATIBLEMSIPACKAGEBEGIN_RESULTS
-{
-    DWORD cbSize;
-    BOOL fCancel;
-    BOOTSTRAPPER_REQUEST_STATE requestedState;
-};
-
-struct BA_ONPLANCOMPATIBLEMSIPACKAGECOMPLETE_ARGS
-{
-    DWORD cbSize;
-    LPCWSTR wzPackageId;
-    LPCWSTR wzCompatiblePackageId;
-    HRESULT hrStatus;
-    BOOTSTRAPPER_PACKAGE_STATE state;
-    BOOTSTRAPPER_REQUEST_STATE requested;
-    BOOTSTRAPPER_ACTION_STATE execute;
-    BOOTSTRAPPER_ACTION_STATE rollback;
-};
-
-struct BA_ONPLANCOMPATIBLEMSIPACKAGECOMPLETE_RESULTS
-{
-    DWORD cbSize;
-};
-
 struct BA_ONPLANCOMPLETE_ARGS
 {
     DWORD cbSize;
diff --git a/src/engine/apply.cpp b/src/engine/apply.cpp
index 8e5099d9..dd4932aa 100644
--- a/src/engine/apply.cpp
+++ b/src/engine/apply.cpp
@@ -199,10 +199,6 @@ static HRESULT ExecuteDependencyAction(
     __in BURN_EXECUTE_ACTION* pAction,
     __in BURN_EXECUTE_CONTEXT* pContext
     );
-static HRESULT ExecuteCompatiblePackageAction(
-    __in BURN_ENGINE_STATE* pEngineState,
-    __in BURN_EXECUTE_ACTION* pAction
-    );
 static HRESULT ExecuteMsiBeginTransaction(
     __in BURN_ENGINE_STATE* pEngineState,
     __in BURN_ROLLBACK_BOUNDARY* pRollbackBoundary,
@@ -1727,11 +1723,6 @@ static HRESULT DoExecuteAction(
             ExitOnFailure(hr, "Failed to execute dependency action.");
             break;
 
-        case BURN_EXECUTE_ACTION_TYPE_COMPATIBLE_PACKAGE:
-            hr = ExecuteCompatiblePackageAction(pEngineState, pExecuteAction);
-            ExitOnFailure(hr, "Failed to execute compatible package action.");
-            break;
-
         case BURN_EXECUTE_ACTION_TYPE_REGISTRATION:
             *pfKeepRegistration = pExecuteAction->registration.fKeep;
             break;
@@ -2183,25 +2174,6 @@ LExit:
     return hr;
 }
 
-static HRESULT ExecuteCompatiblePackageAction(
-    __in BURN_ENGINE_STATE* pEngineState,
-    __in BURN_EXECUTE_ACTION* pAction
-    )
-{
-    HRESULT hr = S_OK;
-
-    if (pAction->compatiblePackage.pReferencePackage->fPerMachine)
-    {
-        hr = ElevationLoadCompatiblePackageAction(pEngineState->companionConnection.hPipe, pAction);
-        ExitOnFailure(hr, "Failed to load compatible package on per-machine package.");
-    }
-
-    // Compatible package already loaded in this process.
-
-LExit:
-    return hr;
-}
-
 static HRESULT ExecuteMsiBeginTransaction(
     __in BURN_ENGINE_STATE* pEngineState,
     __in BURN_ROLLBACK_BOUNDARY* pRollbackBoundary,
diff --git a/src/engine/core.cpp b/src/engine/core.cpp
index 0f5ea08a..77e2dd82 100644
--- a/src/engine/core.cpp
+++ b/src/engine/core.cpp
@@ -1692,14 +1692,6 @@ static void LogPackages(
             LogId(REPORT_STANDARD, MSG_PLANNED_PACKAGE, pPackage->sczId, LoggingPackageStateToString(pPackage->currentState), LoggingRequestStateToString(pPackage->defaultRequested), LoggingRequestStateToString(pPackage->requested), LoggingActionStateToString(pPackage->execute), LoggingActionStateToString(pPackage->rollback), LoggingBoolToString(pPackage->fAcquire), LoggingBoolToString(pPackage->fUncache), LoggingDependencyActionToString(pPackage->dependencyExecute));
         }
 
-        for (DWORD i = 0; i < pPackages->cCompatiblePackages; ++i)
-        {
-            const DWORD iPackage = (BOOTSTRAPPER_ACTION_UNINSTALL == action) ? pPackages->cCompatiblePackages - 1 - i : i;
-            const BURN_PACKAGE* pPackage = &pPackages->rgCompatiblePackages[iPackage];
-
-            LogId(REPORT_STANDARD, MSG_PLANNED_PACKAGE, pPackage->sczId, LoggingPackageStateToString(pPackage->currentState), LoggingRequestStateToString(pPackage->defaultRequested), LoggingRequestStateToString(pPackage->requested), LoggingActionStateToString(pPackage->execute), LoggingActionStateToString(pPackage->rollback), LoggingBoolToString(pPackage->fAcquire), LoggingBoolToString(pPackage->fUncache), LoggingDependencyActionToString(pPackage->dependencyExecute));
-        }
-
         // Display related bundles last if caching, installing, modifying, or repairing.
         if (BOOTSTRAPPER_ACTION_UNINSTALL < action && 0 < pRelatedBundles->cRelatedBundles)
         {
diff --git a/src/engine/detect.cpp b/src/engine/detect.cpp
index 176780af..63e66539 100644
--- a/src/engine/detect.cpp
+++ b/src/engine/detect.cpp
@@ -63,8 +63,6 @@ extern "C" void DetectReset(
 
                 pFeature->currentState = BOOTSTRAPPER_FEATURE_STATE_UNKNOWN;
             }
-
-            pPackage->Msi.fCompatibleInstalled = FALSE;
         }
         else if (BURN_PACKAGE_TYPE_MSP == pPackage->type)
         {
diff --git a/src/engine/elevation.cpp b/src/engine/elevation.cpp
index fc53b1f8..cd0c9387 100644
--- a/src/engine/elevation.cpp
+++ b/src/engine/elevation.cpp
@@ -24,7 +24,6 @@ typedef enum _BURN_ELEVATION_MESSAGE_TYPE
     BURN_ELEVATION_MESSAGE_TYPE_EXECUTE_MSU_PACKAGE,
     BURN_ELEVATION_MESSAGE_TYPE_EXECUTE_PACKAGE_PROVIDER,
     BURN_ELEVATION_MESSAGE_TYPE_EXECUTE_PACKAGE_DEPENDENCY,
-    BURN_ELEVATION_MESSAGE_TYPE_LOAD_COMPATIBLE_PACKAGE,
     BURN_ELEVATION_MESSAGE_TYPE_LAUNCH_EMBEDDED_CHILD,
     BURN_ELEVATION_MESSAGE_TYPE_CLEAN_PACKAGE,
     BURN_ELEVATION_MESSAGE_TYPE_LAUNCH_APPROVED_EXE,
@@ -95,11 +94,6 @@ static HRESULT WaitForElevatedChildCacheThread(
     __in HANDLE hCacheThread,
     __in DWORD dwExpectedExitCode
     );
-static HRESULT OnLoadCompatiblePackage(
-    __in BURN_PACKAGES* pPackages,
-    __in BYTE* pbData,
-    __in DWORD cbData
-    );
 static HRESULT ProcessApplyInitializeMessages(
     __in BURN_PIPE_MESSAGE* pMsg,
     __in_opt LPVOID pvContext,
@@ -1115,45 +1109,6 @@ LExit:
 }
 
 /*******************************************************************
- ElevationLoadCompatiblePackageAction - Load compatible package
-  information from the referenced package.
-
-*******************************************************************/
-extern "C" HRESULT ElevationLoadCompatiblePackageAction(
-    __in HANDLE hPipe,
-    __in BURN_EXECUTE_ACTION* pExecuteAction
-    )
-{
-    HRESULT hr = S_OK;
-    BYTE* pbData = NULL;
-    SIZE_T cbData = 0;
-    DWORD dwResult = 0;
-    BOOTSTRAPPER_APPLY_RESTART restart = BOOTSTRAPPER_APPLY_RESTART_NONE;
-
-    // Serialize message data.
-    hr = BuffWriteString(&pbData, &cbData, pExecuteAction->compatiblePackage.pReferencePackage->sczId);
-    ExitOnFailure(hr, "Failed to write package id to message buffer.");
-
-    hr = BuffWriteString(&pbData, &cbData, pExecuteAction->compatiblePackage.sczInstalledProductCode);
-    ExitOnFailure(hr, "Failed to write installed ProductCode to message buffer.");
-
-    hr = BuffWriteString(&pbData, &cbData, pExecuteAction->compatiblePackage.pInstalledVersion->sczVersion);
-    ExitOnFailure(hr, "Failed to write installed version to message buffer.");
-
-    // Send the message.
-    hr = PipeSendMessage(hPipe, BURN_ELEVATION_MESSAGE_TYPE_LOAD_COMPATIBLE_PACKAGE, pbData, cbData, NULL, NULL, &dwResult);
-    ExitOnFailure(hr, "Failed to send BURN_ELEVATION_MESSAGE_TYPE_LOAD_COMPATIBLE_PACKAGE message to per-machine process.");
-
-    // Ignore the restart since this action only loads data into memory.
-    hr = ProcessResult(dwResult, &restart);
-
-LExit:
-    ReleaseBuffer(pbData);
-
-    return hr;
-}
-
-/*******************************************************************
  ElevationCleanPackage - 
 
 *******************************************************************/
@@ -1719,10 +1674,6 @@ static HRESULT ProcessElevatedChildMessage(
         hrResult = OnExecutePackageDependencyAction(pContext->pPackages, &pContext->pRegistration->relatedBundles, (BYTE*)pMsg->pvData, pMsg->cbData);
         break;
 
-    case BURN_ELEVATION_MESSAGE_TYPE_LOAD_COMPATIBLE_PACKAGE:
-        hrResult = OnLoadCompatiblePackage(pContext->pPackages, (BYTE*)pMsg->pvData, pMsg->cbData);
-        break;
-
     case BURN_ELEVATION_MESSAGE_TYPE_CLEAN_PACKAGE:
         hrResult = OnCleanPackage(pContext->pPackages, (BYTE*)pMsg->pvData, pMsg->cbData);
         break;
@@ -2636,55 +2587,6 @@ LExit:
     return hr;
 }
 
-static HRESULT OnLoadCompatiblePackage(
-    __in BURN_PACKAGES* pPackages,
-    __in BYTE* pbData,
-    __in DWORD cbData
-    )
-{
-    HRESULT hr = S_OK;
-    SIZE_T iData = 0;
-    LPWSTR sczPackage = NULL;
-    LPWSTR sczVersion = NULL;
-    BURN_EXECUTE_ACTION executeAction = { };
-
-    executeAction.type = BURN_EXECUTE_ACTION_TYPE_COMPATIBLE_PACKAGE;
-
-    // Deserialize the message data.
-    hr = BuffReadString(pbData, cbData, &iData, &sczPackage);
-    ExitOnFailure(hr, "Failed to read package id from message buffer.");
-
-    // Find the reference package.
-    hr = PackageFindById(pPackages, sczPackage, &executeAction.compatiblePackage.pReferencePackage);
-    ExitOnFailure(hr, "Failed to find package: %ls", sczPackage);
-
-    hr = BuffReadString(pbData, cbData, &iData, &executeAction.compatiblePackage.sczInstalledProductCode);
-    ExitOnFailure(hr, "Failed to read installed ProductCode from message buffer.");
-
-    hr = BuffReadString(pbData, cbData, &iData, &sczVersion);
-    ExitOnFailure(hr, "Failed to read installed version from message buffer.");
-
-    hr = VerParseVersion(sczVersion, 0, FALSE, &executeAction.compatiblePackage.pInstalledVersion);
-    ExitOnFailure(hr, "Failed to parse installed version from compatible package.");
-
-    // Copy the installed data to the reference package.
-    hr = StrAllocString(&executeAction.compatiblePackage.pReferencePackage->Msi.sczInstalledProductCode, executeAction.compatiblePackage.sczInstalledProductCode, 0);
-    ExitOnFailure(hr, "Failed to copy installed ProductCode.");
-
-    executeAction.compatiblePackage.pReferencePackage->Msi.pInstalledVersion = executeAction.compatiblePackage.pInstalledVersion;
-
-    // Load the compatible package and add it to the list.
-    hr = MsiEngineAddCompatiblePackage(pPackages, executeAction.compatiblePackage.pReferencePackage, NULL);
-    ExitOnFailure(hr, "Failed to load compatible package.");
-
-LExit:
-    ReleaseStr(sczVersion);
-    ReleaseStr(sczPackage);
-    PlanUninitializeExecuteAction(&executeAction);
-
-    return hr;
-}
-
 static int GenericExecuteMessageHandler(
     __in GENERIC_EXECUTE_MESSAGE* pMessage,
     __in LPVOID pvContext
diff --git a/src/engine/elevation.h b/src/engine/elevation.h
index 05fecdf6..e254dea5 100644
--- a/src/engine/elevation.h
+++ b/src/engine/elevation.h
@@ -117,10 +117,6 @@ HRESULT ElevationExecutePackageDependencyAction(
     __in HANDLE hPipe,
     __in BURN_EXECUTE_ACTION* pExecuteAction
     );
-HRESULT ElevationLoadCompatiblePackageAction(
-    __in HANDLE hPipe,
-    __in BURN_EXECUTE_ACTION* pExecuteAction
-    );
 HRESULT ElevationLaunchElevatedChild(
     __in HANDLE hPipe,
     __in BURN_PACKAGE* pPackage,
diff --git a/src/engine/engine.mc b/src/engine/engine.mc
index 8e36e84e..ad86308c 100644
--- a/src/engine/engine.mc
+++ b/src/engine/engine.mc
@@ -226,13 +226,6 @@ Language=English
 Detected forward compatible bundle: %1!ls!, type: %2!hs!, scope: %3!hs!, version: %4!ls!, enabled: %5!hs!
 .
 
-MessageId=108
-Severity=Success
-SymbolicName=MSG_DETECTED_COMPATIBLE_PACKAGE_FROM_PROVIDER
-Language=English
-Detected compatible package: %1!ls!, provider: %2!ls!, installed: %3!ls!, version: %4!ls!, chained: %5!ls!
-.
-
 MessageId=120
 Severity=Warning
 SymbolicName=MSG_DETECT_PACKAGE_NOT_FULLY_CACHED
@@ -394,13 +387,6 @@ Language=English
 Plan skipped related bundle: %1!ls!, type: %2!hs!, because it was previously scheduled.
 .
 
-MessageId=215
-Severity=Success
-SymbolicName=MSG_PLANNED_ORPHAN_PACKAGE_FROM_PROVIDER
-Language=English
-Will remove orphan package: %1!ls!, installed: %2!ls!, chained: %3!ls!
-.
-
 MessageId=216
 Severity=Success
 SymbolicName=MSG_PLAN_SKIPPED_RELATED_BUNDLE_EMBEDDED_BUNDLE_NEWER
diff --git a/src/engine/msiengine.cpp b/src/engine/msiengine.cpp
index 688be7af..5bccb375 100644
--- a/src/engine/msiengine.cpp
+++ b/src/engine/msiengine.cpp
@@ -325,7 +325,6 @@ extern "C" void MsiEnginePackageUninitialize(
 {
     ReleaseStr(pPackage->Msi.sczProductCode);
     ReleaseStr(pPackage->Msi.sczUpgradeCode);
-    ReleaseStr(pPackage->Msi.sczInstalledProductCode);
 
     // free features
     if (pPackage->Msi.rgFeatures)
@@ -404,8 +403,6 @@ extern "C" HRESULT MsiEngineDetectPackage(
     int nCompareResult = 0;
     LPWSTR sczInstalledVersion = NULL;
     LPWSTR sczInstalledLanguage = NULL;
-    LPWSTR sczInstalledProductCode = NULL;
-    LPWSTR sczInstalledProviderKey = NULL;
     INSTALLSTATE installState = INSTALLSTATE_UNKNOWN;
     BOOTSTRAPPER_RELATED_OPERATION operation = BOOTSTRAPPER_RELATED_OPERATION_NONE;
     BOOTSTRAPPER_RELATED_OPERATION relatedMsiOperation = BOOTSTRAPPER_RELATED_OPERATION_NONE;
@@ -457,42 +454,6 @@ extern "C" HRESULT MsiEngineDetectPackage(
     }
     else if (HRESULT_FROM_WIN32(ERROR_UNKNOWN_PRODUCT) == hr || HRESULT_FROM_WIN32(ERROR_UNKNOWN_PROPERTY) == hr) // package not present.
     {
-        // Check for newer, compatible packages based on a fixed provider key.
-        hr = DependencyDetectProviderKeyPackageId(pPackage, &sczInstalledProviderKey, &sczInstalledProductCode);
-        if (SUCCEEDED(hr))
-        {
-            hr = WiuGetProductInfoEx(sczInstalledProductCode, NULL, pPackage->fPerMachine ? MSIINSTALLCONTEXT_MACHINE : MSIINSTALLCONTEXT_USERUNMANAGED, INSTALLPROPERTY_VERSIONSTRING, &sczInstalledVersion);
-            if (SUCCEEDED(hr))
-            {
-                hr = VerParseVersion(sczInstalledVersion, 0, FALSE, &pVersion);
-                ExitOnFailure(hr, "Failed to parse dependency version: '%ls' for ProductCode: %ls", sczInstalledVersion, sczInstalledProductCode);
-
-                if (pVersion->fInvalid)
-                {
-                    LogId(REPORT_WARNING, MSG_DETECTED_MSI_PACKAGE_INVALID_VERSION, sczInstalledProductCode, sczInstalledVersion);
-                }
-
-                // compare versions
-                hr = VerCompareParsedVersions(pPackage->Msi.pVersion, pVersion, &nCompareResult);
-                ExitOnFailure(hr, "Failed to compare version '%ls' to dependency version: '%ls'", pPackage->Msi.pVersion->sczVersion, pVersion->sczVersion);
-
-                if (nCompareResult < 0)
-                {
-                    LogId(REPORT_STANDARD, MSG_DETECTED_COMPATIBLE_PACKAGE_FROM_PROVIDER, pPackage->sczId, sczInstalledProviderKey, sczInstalledProductCode, sczInstalledVersion, pPackage->Msi.sczProductCode);
-
-                    hr = UserExperienceOnDetectCompatibleMsiPackage(pUserExperience, pPackage->sczId, sczInstalledProductCode, pVersion);
-                    ExitOnRootFailure(hr, "BA aborted detect compatible MSI package.");
-
-                    hr = StrAllocString(&pPackage->Msi.sczInstalledProductCode, sczInstalledProductCode, 0);
-                    ExitOnFailure(hr, "Failed to copy the installed ProductCode to the package.");
-
-                    pPackage->Msi.pInstalledVersion = pVersion;
-                    pPackage->Msi.fCompatibleInstalled = TRUE;
-                    pVersion = NULL;
-                }
-            }
-        }
-
         pPackage->currentState = BOOTSTRAPPER_PACKAGE_STATE_ABSENT;
         hr = S_OK;
     }
@@ -701,8 +662,6 @@ extern "C" HRESULT MsiEngineDetectPackage(
     }
 
 LExit:
-    ReleaseStr(sczInstalledProviderKey);
-    ReleaseStr(sczInstalledProductCode);
     ReleaseStr(sczInstalledLanguage);
     ReleaseStr(sczInstalledVersion);
     ReleaseVerutilVersion(pVersion);
@@ -1023,121 +982,6 @@ LExit:
     return hr;
 }
 
-extern "C" HRESULT MsiEngineAddCompatiblePackage(
-    __in BURN_PACKAGES* pPackages,
-    __in const BURN_PACKAGE* pPackage,
-    __out_opt BURN_PACKAGE** ppCompatiblePackage
-    )
-{
-    Assert(BURN_PACKAGE_TYPE_MSI == pPackage->type);
-
-    HRESULT hr = S_OK;
-    BURN_PACKAGE* pCompatiblePackage = NULL;
-    LPWSTR sczInstalledVersion = NULL;
-
-    // Allocate enough memory all at once so pointers to packages within
-    // aren't invalidated if we otherwise reallocated.
-    hr = PackageEnsureCompatiblePackagesArray(pPackages);
-    ExitOnFailure(hr, "Failed to allocate memory for compatible MSI package.");
-
-    pCompatiblePackage = pPackages->rgCompatiblePackages + pPackages->cCompatiblePackages;
-    ++pPackages->cCompatiblePackages;
-
-    pCompatiblePackage->type = BURN_PACKAGE_TYPE_MSI;
-
-    // Read in the compatible ProductCode if not already available.
-    if (pPackage->Msi.sczInstalledProductCode)
-    {
-        hr = StrAllocString(&pCompatiblePackage->Msi.sczProductCode, pPackage->Msi.sczInstalledProductCode, 0);
-        ExitOnFailure(hr, "Failed to copy installed ProductCode to compatible package.");
-    }
-    else
-    {
-        hr = DependencyDetectProviderKeyPackageId(pPackage, NULL, &pCompatiblePackage->Msi.sczProductCode);
-        ExitOnFailure(hr, "Failed to detect compatible package from provider key.");
-    }
-
-    // Read in the compatible ProductVersion if not already available.
-    if (pPackage->Msi.pInstalledVersion)
-    {
-        hr = VerCopyVersion(pPackage->Msi.pInstalledVersion, &pCompatiblePackage->Msi.pVersion);
-        ExitOnFailure(hr, "Failed to copy version for compatible package.");
-    }
-    else
-    {
-        hr = WiuGetProductInfoEx(pCompatiblePackage->Msi.sczProductCode, NULL, pPackage->fPerMachine ? MSIINSTALLCONTEXT_MACHINE : MSIINSTALLCONTEXT_USERUNMANAGED, INSTALLPROPERTY_VERSIONSTRING, &sczInstalledVersion);
-        ExitOnFailure(hr, "Failed to read version from compatible package.");
-
-        hr = VerParseVersion(sczInstalledVersion, 0, FALSE, &pCompatiblePackage->Msi.pVersion);
-        ExitOnFailure(hr, "Failed to parse version: '%ls' for ProductCode: %ls", sczInstalledVersion, pCompatiblePackage->Msi.sczProductCode);
-
-        if (pCompatiblePackage->Msi.pVersion->fInvalid)
-        {
-            LogId(REPORT_WARNING, MSG_DETECTED_MSI_PACKAGE_INVALID_VERSION, pCompatiblePackage->Msi.sczProductCode, sczInstalledVersion);
-        }
-    }
-
-    // For now, copy enough information to support uninstalling the newer, compatible package.
-    hr = StrAllocString(&pCompatiblePackage->sczId, pCompatiblePackage->Msi.sczProductCode, 0);
-    ExitOnFailure(hr, "Failed to copy installed ProductCode as compatible package ID.");
-
-    pCompatiblePackage->fPerMachine = pPackage->fPerMachine;
-    pCompatiblePackage->fUninstallable = pPackage->fUninstallable;
-    pCompatiblePackage->cacheType = pPackage->cacheType;
-
-    // Removing compatible packages is best effort.
-    pCompatiblePackage->fVital = FALSE;
-
-    // Format a suitable log path variable from the original package.
-    hr = StrAllocFormatted(&pCompatiblePackage->sczLogPathVariable, L"%ls_Compatible", pPackage->sczLogPathVariable);
-    ExitOnFailure(hr, "Failed to format log path variable for compatible package.");
-
-    // Use the default cache ID generation from the binder.
-    hr = StrAllocFormatted(&pCompatiblePackage->sczCacheId, L"%lsv%ls", pCompatiblePackage->sczId, pCompatiblePackage->Msi.pVersion->sczVersion);
-    ExitOnFailure(hr, "Failed to format cache ID for compatible package.");
-
-    pCompatiblePackage->currentState = BOOTSTRAPPER_PACKAGE_STATE_PRESENT;
-    pCompatiblePackage->cache = BURN_CACHE_STATE_PARTIAL; // Cannot know if it's complete or not.
-
-    // Copy all the providers to ensure no dependents.
-    if (pPackage->cDependencyProviders)
-    {
-        pCompatiblePackage->rgDependencyProviders = (BURN_DEPENDENCY_PROVIDER*)MemAlloc(sizeof(BURN_DEPENDENCY_PROVIDER) * pPackage->cDependencyProviders, TRUE);
-        ExitOnNull(pCompatiblePackage->rgDependencyProviders, hr, E_OUTOFMEMORY, "Failed to allocate for compatible package providers.");
-
-        for (DWORD i = 0; i < pPackage->cDependencyProviders; ++i)
-        {
-            BURN_DEPENDENCY_PROVIDER* pProvider = pPackage->rgDependencyProviders + i;
-            BURN_DEPENDENCY_PROVIDER* pCompatibleProvider = pCompatiblePackage->rgDependencyProviders + i;
-
-            // Only need to copy the key for uninstall.
-            hr = StrAllocString(&pCompatibleProvider->sczKey, pProvider->sczKey, 0);
-            ExitOnFailure(hr, "Failed to copy the compatible provider key.");
-
-            // Assume the package version is the same as the provider version.
-            hr = StrAllocString(&pCompatibleProvider->sczVersion, pCompatiblePackage->Msi.pVersion->sczVersion, 0);
-            ExitOnFailure(hr, "Failed to copy the compatible provider version.");
-
-            // Assume provider keys are similarly authored for this package.
-            pCompatibleProvider->fImported = pProvider->fImported;
-        }
-
-        pCompatiblePackage->cDependencyProviders = pPackage->cDependencyProviders;
-    }
-
-    pCompatiblePackage->type = BURN_PACKAGE_TYPE_MSI;
-
-    if (ppCompatiblePackage)
-    {
-        *ppCompatiblePackage = pCompatiblePackage;
-    }
-
-LExit:
-    ReleaseStr(sczInstalledVersion);
-
-    return hr;
-}
-
 extern "C" HRESULT MsiEngineBeginTransaction(
     __in LPCWSTR wzName
     )
diff --git a/src/engine/msiengine.h b/src/engine/msiengine.h
index c7cc3bef..1f450147 100644
--- a/src/engine/msiengine.h
+++ b/src/engine/msiengine.h
@@ -48,11 +48,6 @@ HRESULT MsiEnginePlanAddPackage(
     __in_opt HANDLE hCacheEvent,
     __in BOOL fPlanPackageCacheRollback
     );
-HRESULT MsiEngineAddCompatiblePackage(
-    __in BURN_PACKAGES* pPackages,
-    __in const BURN_PACKAGE* pPackage,
-    __out_opt BURN_PACKAGE** ppCompatiblePackage
-    );
 HRESULT MsiEngineBeginTransaction(
     __in LPCWSTR wzName
     );
diff --git a/src/engine/package.cpp b/src/engine/package.cpp
index 02958efd..527766eb 100644
--- a/src/engine/package.cpp
+++ b/src/engine/package.cpp
@@ -369,15 +369,6 @@ extern "C" void PackagesUninitialize(
         MemFree(pPackages->rgPackages);
     }
 
-    if (pPackages->rgCompatiblePackages)
-    {
-        for (DWORD i = 0; i < pPackages->cCompatiblePackages; ++i)
-        {
-            PackageUninitialize(pPackages->rgCompatiblePackages + i);
-        }
-        MemFree(pPackages->rgCompatiblePackages);
-    }
-
     if (pPackages->rgPatchTargetCodes)
     {
         for (DWORD i = 0; i < pPackages->cPatchTargetCodes; ++i)
@@ -414,17 +405,6 @@ extern "C" HRESULT PackageFindById(
         }
     }
 
-    for (DWORD i = 0; i < pPackages->cCompatiblePackages; ++i)
-    {
-        pPackage = &pPackages->rgCompatiblePackages[i];
-
-        if (CSTR_EQUAL == ::CompareStringW(LOCALE_INVARIANT, 0, pPackage->sczId, -1, wzId, -1))
-        {
-            *ppPackage = pPackage;
-            ExitFunction1(hr = S_OK);
-        }
-    }
-
     hr = E_NOTFOUND;
 
 LExit:
@@ -510,22 +490,6 @@ LExit:
     return hr;
 }
 
-HRESULT PackageEnsureCompatiblePackagesArray(
-    __in BURN_PACKAGES* pPackages
-    )
-{
-    HRESULT hr = S_OK;
-
-    if (!pPackages->rgCompatiblePackages)
-    {
-        pPackages->rgCompatiblePackages = (BURN_PACKAGE*)MemAlloc(sizeof(BURN_PACKAGE) * pPackages->cPackages, TRUE);
-        ExitOnNull(pPackages->rgCompatiblePackages, hr, E_OUTOFMEMORY, "Failed to allocate memory for compatible packages.");
-    }
-
-LExit:
-    return hr;
-}
-
 
 // internal function declarations
 
diff --git a/src/engine/package.h b/src/engine/package.h
index ec176f8c..1a4f7060 100644
--- a/src/engine/package.h
+++ b/src/engine/package.h
@@ -248,7 +248,6 @@ typedef struct _BURN_PACKAGE
             LPWSTR sczProductCode;
             DWORD dwLanguage;
             VERUTIL_VERSION* pVersion;
-            LPWSTR sczInstalledProductCode;
             VERUTIL_VERSION* pInstalledVersion;
             LPWSTR sczUpgradeCode;
 
@@ -264,8 +263,6 @@ typedef struct _BURN_PACKAGE
             _BURN_PACKAGE** rgpSlipstreamMspPackages;
             LPWSTR* rgsczSlipstreamMspPackageIds;
             DWORD cSlipstreamMspPackages;
-
-            BOOL fCompatibleInstalled;
         } Msi;
         struct
         {
@@ -294,9 +291,6 @@ typedef struct _BURN_PACKAGES
     BURN_PACKAGE* rgPackages;
     DWORD cPackages;
 
-    BURN_PACKAGE* rgCompatiblePackages;
-    DWORD cCompatiblePackages;
-
     BURN_PATCH_TARGETCODE* rgPatchTargetCodes;
     DWORD cPatchTargetCodes;
 
@@ -335,9 +329,6 @@ HRESULT PackageGetProperty(
     __in_z LPCWSTR wzProperty,
     __out_z_opt LPWSTR* psczValue
     );
-HRESULT PackageEnsureCompatiblePackagesArray(
-    __in BURN_PACKAGES* pPackages
-    );
 
 
 #if defined(__cplusplus)
diff --git a/src/engine/plan.cpp b/src/engine/plan.cpp
index ffbe495f..a45eab62 100644
--- a/src/engine/plan.cpp
+++ b/src/engine/plan.cpp
@@ -30,7 +30,6 @@ static void ResetPlannedRollbackBoundaryState(
     );
 static HRESULT ProcessPackage(
     __in BOOL fBundlePerMachine,
-    __in_opt BURN_PACKAGE* pCompatiblePackageParent,
     __in BURN_USER_EXPERIENCE* pUX,
     __in BURN_PLAN* pPlan,
     __in BURN_PACKAGE* pPackage,
@@ -311,10 +310,6 @@ extern "C" void PlanUninitializeExecuteAction(
     case BURN_EXECUTE_ACTION_TYPE_PACKAGE_DEPENDENCY:
         ReleaseStr(pExecuteAction->packageDependency.sczBundleProviderKey);
         break;
-
-    case BURN_EXECUTE_ACTION_TYPE_COMPATIBLE_PACKAGE:
-        ReleaseStr(pExecuteAction->compatiblePackage.sczInstalledProductCode);
-        break;
     }
 }
 
@@ -523,39 +518,8 @@ extern "C" HRESULT PlanPackages(
             }
         }
 
-        hr = ProcessPackage(fBundlePerMachine, NULL, pUX, pPlan, pPackage, pLog, pVariables, display, relationType, wzLayoutDirectory, phSyncpointEvent, &pRollbackBoundary, &nonpermanentPackageIndices);
+        hr = ProcessPackage(fBundlePerMachine, pUX, pPlan, pPackage, pLog, pVariables, display, relationType, wzLayoutDirectory, phSyncpointEvent, &pRollbackBoundary, &nonpermanentPackageIndices);
         ExitOnFailure(hr, "Failed to process package.");
-
-        // Attempt to remove orphaned packages during uninstall. Currently only MSI packages are supported and should not require source.
-        if (BOOTSTRAPPER_ACTION_UNINSTALL == pPlan->action && BURN_PACKAGE_TYPE_MSI == pPackage->type && pPackage->Msi.fCompatibleInstalled)
-        {
-            BURN_PACKAGE* pCompatiblePackage = NULL;
-            BURN_EXECUTE_ACTION* pAction = NULL;
-
-            // Add the compatible package to the list.
-            hr = MsiEngineAddCompatiblePackage(pPackages, pPackage, &pCompatiblePackage);
-            ExitOnFailure(hr, "Failed to add compatible package for package: %ls", pPackage->sczId);
-
-            // Plan to load the compatible package into the elevated engine before its needed.
-            hr = PlanAppendExecuteAction(pPlan, &pAction);
-            ExitOnFailure(hr, "Failed to append execute action.");
-
-            pAction->type = BURN_EXECUTE_ACTION_TYPE_COMPATIBLE_PACKAGE;
-            pAction->compatiblePackage.pReferencePackage = pPackage;
-            pAction->compatiblePackage.pInstalledVersion = pCompatiblePackage->Msi.pVersion;
-
-            hr = StrAllocString(&pAction->compatiblePackage.sczInstalledProductCode, pCompatiblePackage->Msi.sczProductCode, 0);
-            ExitOnFailure(hr, "Failed to copy installed ProductCode");
-
-            // Process the compatible MSI package like any other.
-            hr = ProcessPackage(fBundlePerMachine, pPackage, pUX, pPlan, pCompatiblePackage, pLog, pVariables, display, relationType, wzLayoutDirectory, phSyncpointEvent, &pRollbackBoundary, &nonpermanentPackageIndices);
-            ExitOnFailure(hr, "Failed to process compatible package.");
-
-            if (BOOTSTRAPPER_ACTION_STATE_UNINSTALL == pCompatiblePackage->execute)
-            {
-                LogId(REPORT_STANDARD, MSG_PLANNED_ORPHAN_PACKAGE_FROM_PROVIDER, pPackage->sczId, pCompatiblePackage->Msi.sczProductCode, pPackage->Msi.sczProductCode);
-            }
-        }
     }
 
     // Insert the "keep registration" and "remove registration" actions in the plan when installing the first time and anytime we are uninstalling respectively.
@@ -601,15 +565,6 @@ extern "C" HRESULT PlanPackages(
         ExitOnFailure(hr, "Failed to plan clean package.");
     }
 
-    // Plan best-effort clean up of compatible packages.
-    for (DWORD i = 0; i < pPackages->cCompatiblePackages; ++i)
-    {
-        DWORD iPackage = (BOOTSTRAPPER_ACTION_UNINSTALL == pPlan->action) ? pPackages->cCompatiblePackages - 1 - i : i;
-        BURN_PACKAGE* pCompatiblePackage = pPackages->rgCompatiblePackages + iPackage;
-
-        PlanCleanPackage(pPlan, pCompatiblePackage);
-    }
-
 LExit:
     return hr;
 }
@@ -809,7 +764,7 @@ extern "C" HRESULT PlanPassThroughBundle(
     BURN_ROLLBACK_BOUNDARY* pRollbackBoundary = NULL;
 
     // Plan passthrough package.
-    hr = ProcessPackage(fBundlePerMachine, NULL, pUX, pPlan, pPackage, pLog, pVariables, display, relationType, NULL, phSyncpointEvent, &pRollbackBoundary, NULL);
+    hr = ProcessPackage(fBundlePerMachine, pUX, pPlan, pPackage, pLog, pVariables, display, relationType, NULL, phSyncpointEvent, &pRollbackBoundary, NULL);
     ExitOnFailure(hr, "Failed to process passthrough package.");
 
     // If we still have an open rollback boundary, complete it.
@@ -843,7 +798,7 @@ extern "C" HRESULT PlanUpdateBundle(
     BURN_ROLLBACK_BOUNDARY* pRollbackBoundary = NULL;
 
     // Plan update package.
-    hr = ProcessPackage(fBundlePerMachine, NULL, pUX, pPlan, pPackage, pLog, pVariables, display, relationType, NULL, phSyncpointEvent, &pRollbackBoundary, NULL);
+    hr = ProcessPackage(fBundlePerMachine, pUX, pPlan, pPackage, pLog, pVariables, display, relationType, NULL, phSyncpointEvent, &pRollbackBoundary, NULL);
     ExitOnFailure(hr, "Failed to process update package.");
 
     // If we still have an open rollback boundary, complete it.
@@ -863,7 +818,6 @@ LExit:
 
 static HRESULT ProcessPackage(
     __in BOOL fBundlePerMachine,
-    __in_opt BURN_PACKAGE* pCompatiblePackageParent,
     __in BURN_USER_EXPERIENCE* pUX,
     __in BURN_PLAN* pPlan,
     __in BURN_PACKAGE* pPackage,
@@ -888,18 +842,8 @@ static HRESULT ProcessPackage(
     pPackage->requested = pPackage->defaultRequested;
     fPlanPackageBegan = TRUE;
 
-    if (pCompatiblePackageParent)
-    {
-        AssertSz(BURN_PACKAGE_TYPE_MSI == pPackage->type, "Currently only MSI packages have compatible packages.");
-
-        hr = UserExperienceOnPlanCompatibleMsiPackageBegin(pUX, pCompatiblePackageParent->sczId, pPackage->sczId, pPackage->Msi.pVersion, &pPackage->requested);
-        ExitOnRootFailure(hr, "BA aborted plan compatible MSI package begin.");
-    }
-    else
-    {
-        hr = UserExperienceOnPlanPackageBegin(pUX, pPackage->sczId, &pPackage->requested);
-        ExitOnRootFailure(hr, "BA aborted plan package begin.");
-    }
+    hr = UserExperienceOnPlanPackageBegin(pUX, pPackage->sczId, &pPackage->requested);
+    ExitOnRootFailure(hr, "BA aborted plan package begin.");
 
     pEffectiveRollbackBoundary = (BOOTSTRAPPER_ACTION_UNINSTALL == pPlan->action) ? pPackage->pRollbackBoundaryBackward : pPackage->pRollbackBoundaryForward;
     hr = ProcessPackageRollbackBoundary(pPlan, pEffectiveRollbackBoundary, ppRollbackBoundary);
@@ -964,14 +908,7 @@ static HRESULT ProcessPackage(
 LExit:
     if (fPlanPackageBegan)
     {
-        if (pCompatiblePackageParent)
-        {
-            UserExperienceOnPlanCompatibleMsiPackageComplete(pUX, pCompatiblePackageParent->sczId, pPackage->sczId, hr, pPackage->currentState, pPackage->requested, pPackage->execute, pPackage->rollback);
-        }
-        else
-        {
-            UserExperienceOnPlanPackageComplete(pUX, pPackage->sczId, hr, pPackage->currentState, pPackage->requested, pPackage->execute, pPackage->rollback);
-        }
+        UserExperienceOnPlanPackageComplete(pUX, pPackage->sczId, hr, pPackage->currentState, pPackage->requested, pPackage->execute, pPackage->rollback);
     }
 
     return hr;
@@ -3175,10 +3112,6 @@ static void ExecuteActionLog(
         LogStringLine(PlanDumpLevel, "%ls action[%u]: UNCACHE_PACKAGE id: %ls", wzBase, iAction, pAction->uncachePackage.pPackage->sczId);
         break;
 
-    case BURN_EXECUTE_ACTION_TYPE_COMPATIBLE_PACKAGE:
-        LogStringLine(PlanDumpLevel, "%ls action[%u]: COMPATIBLE_PACKAGE reference id: %ls, installed ProductCode: %ls", wzBase, iAction, pAction->compatiblePackage.pReferencePackage->sczId, pAction->compatiblePackage.sczInstalledProductCode);
-        break;
-
     case BURN_EXECUTE_ACTION_TYPE_BEGIN_MSI_TRANSACTION:
         LogStringLine(PlanDumpLevel, "%ls action[%u]: BEGIN_MSI_TRANSACTION id: %ls", wzBase, iAction, pAction->msiTransaction.pRollbackBoundary->sczId);
         break;
diff --git a/src/engine/plan.h b/src/engine/plan.h
index dad436d4..cb64f891 100644
--- a/src/engine/plan.h
+++ b/src/engine/plan.h
@@ -65,7 +65,6 @@ enum BURN_EXECUTE_ACTION_TYPE
     BURN_EXECUTE_ACTION_TYPE_PACKAGE_DEPENDENCY,
     BURN_EXECUTE_ACTION_TYPE_ROLLBACK_BOUNDARY,
     BURN_EXECUTE_ACTION_TYPE_REGISTRATION,
-    BURN_EXECUTE_ACTION_TYPE_COMPATIBLE_PACKAGE,
     BURN_EXECUTE_ACTION_TYPE_BEGIN_MSI_TRANSACTION,
     BURN_EXECUTE_ACTION_TYPE_COMMIT_MSI_TRANSACTION,
 };
@@ -302,12 +301,6 @@ typedef struct _BURN_EXECUTE_ACTION
         } packageDependency;
         struct
         {
-            BURN_PACKAGE* pReferencePackage;
-            LPWSTR sczInstalledProductCode;
-            VERUTIL_VERSION* pInstalledVersion;
-        } compatiblePackage;
-        struct
-        {
             BURN_ROLLBACK_BOUNDARY* pRollbackBoundary;
         } msiTransaction;
     };
diff --git a/src/engine/userexperience.cpp b/src/engine/userexperience.cpp
index 8e782e71..ea8b8a19 100644
--- a/src/engine/userexperience.cpp
+++ b/src/engine/userexperience.cpp
@@ -104,7 +104,7 @@ extern "C" HRESULT UserExperienceLoad(
     args.pCommand = pCommand;
     args.pfnBootstrapperEngineProc = EngineForApplicationProc;
     args.pvBootstrapperEngineProcContext = pEngineContext;
-    args.qwEngineAPIVersion = MAKEQWORDVERSION(2020, 11, 17, 0);
+    args.qwEngineAPIVersion = MAKEQWORDVERSION(2021, 1, 30, 0);
 
     results.cbSize = sizeof(BOOTSTRAPPER_CREATE_RESULTS);
 
@@ -747,36 +747,6 @@ LExit:
     return hr;
 }
 
-EXTERN_C BAAPI UserExperienceOnDetectCompatibleMsiPackage(
-    __in BURN_USER_EXPERIENCE* pUserExperience,
-    __in_z LPCWSTR wzPackageId,
-    __in_z LPCWSTR wzCompatiblePackageId,
-    __in VERUTIL_VERSION* pCompatiblePackageVersion
-    )
-{
-    HRESULT hr = S_OK;
-    BA_ONDETECTCOMPATIBLEMSIPACKAGE_ARGS args = { };
-    BA_ONDETECTCOMPATIBLEMSIPACKAGE_RESULTS results = { };
-
-    args.cbSize = sizeof(args);
-    args.wzPackageId = wzPackageId;
-    args.wzCompatiblePackageId = wzCompatiblePackageId;
-    args.wzCompatiblePackageVersion = pCompatiblePackageVersion->sczVersion;
-
-    results.cbSize = sizeof(results);
-
-    hr = SendBAMessage(pUserExperience, BOOTSTRAPPER_APPLICATION_MESSAGE_ONDETECTCOMPATIBLEMSIPACKAGE, &args, &results);
-    ExitOnFailure(hr, "BA OnDetectCompatibleMsiPackage failed.");
-
-    if (results.fCancel)
-    {
-        hr = HRESULT_FROM_WIN32(ERROR_INSTALL_USEREXIT);
-    }
-
-LExit:
-    return hr;
-}
-
 EXTERN_C BAAPI UserExperienceOnDetectComplete(
     __in BURN_USER_EXPERIENCE* pUserExperience,
     __in HRESULT hrStatus
@@ -1555,73 +1525,6 @@ LExit:
     return hr;
 }
 
-EXTERN_C BAAPI UserExperienceOnPlanCompatibleMsiPackageBegin(
-    __in BURN_USER_EXPERIENCE* pUserExperience,
-    __in_z LPCWSTR wzPackageId,
-    __in_z LPCWSTR wzCompatiblePackageId,
-    __in VERUTIL_VERSION* pCompatiblePackageVersion,
-    __inout BOOTSTRAPPER_REQUEST_STATE* pRequestedState
-    )
-{
-    HRESULT hr = S_OK;
-    BA_ONPLANCOMPATIBLEMSIPACKAGEBEGIN_ARGS args = { };
-    BA_ONPLANCOMPATIBLEMSIPACKAGEBEGIN_RESULTS results = { };
-
-    args.cbSize = sizeof(args);
-    args.wzPackageId = wzPackageId;
-    args.wzCompatiblePackageId = wzCompatiblePackageId;
-    args.wzCompatiblePackageVersion = pCompatiblePackageVersion->sczVersion;
-    args.recommendedState = *pRequestedState;
-
-    results.cbSize = sizeof(results);
-    results.requestedState = *pRequestedState;
-
-    hr = SendBAMessage(pUserExperience, BOOTSTRAPPER_APPLICATION_MESSAGE_ONPLANCOMPATIBLEMSIPACKAGEBEGIN, &args, &results);
-    ExitOnFailure(hr, "BA OnPlanCompatibleMsiPackageBegin failed.");
-
-    if (results.fCancel)
-    {
-        hr = HRESULT_FROM_WIN32(ERROR_INSTALL_USEREXIT);
-    }
-    *pRequestedState = results.requestedState;
-
-LExit:
-    return hr;
-}
-
-EXTERN_C BAAPI UserExperienceOnPlanCompatibleMsiPackageComplete(
-    __in BURN_USER_EXPERIENCE* pUserExperience,
-    __in_z LPCWSTR wzPackageId,
-    __in_z LPCWSTR wzCompatiblePackageId,
-    __in HRESULT hrStatus,
-    __in BOOTSTRAPPER_PACKAGE_STATE state,
-    __in BOOTSTRAPPER_REQUEST_STATE requested,
-    __in BOOTSTRAPPER_ACTION_STATE execute,
-    __in BOOTSTRAPPER_ACTION_STATE rollback
-    )
-{
-    HRESULT hr = S_OK;
-    BA_ONPLANCOMPATIBLEMSIPACKAGECOMPLETE_ARGS args = { };
-    BA_ONPLANCOMPATIBLEMSIPACKAGECOMPLETE_RESULTS results = { };
-
-    args.cbSize = sizeof(args);
-    args.wzPackageId = wzPackageId;
-    args.wzCompatiblePackageId = wzCompatiblePackageId;
-    args.hrStatus = hrStatus;
-    args.state = state;
-    args.requested = requested;
-    args.execute = execute;
-    args.rollback = rollback;
-
-    results.cbSize = sizeof(results);
-
-    hr = SendBAMessage(pUserExperience, BOOTSTRAPPER_APPLICATION_MESSAGE_ONPLANCOMPATIBLEMSIPACKAGECOMPLETE, &args, &results);
-    ExitOnFailure(hr, "BA OnPlanCompatibleMsiPackageComplete failed.");
-
-LExit:
-    return hr;
-}
-
 EXTERN_C BAAPI UserExperienceOnPlanMsiFeature(
     __in BURN_USER_EXPERIENCE* pUserExperience,
     __in_z LPCWSTR wzPackageId,
diff --git a/src/engine/userexperience.h b/src/engine/userexperience.h
index a02d968c..3176e762 100644
--- a/src/engine/userexperience.h
+++ b/src/engine/userexperience.h
@@ -185,12 +185,6 @@ BAAPI UserExperienceOnDetectBegin(
     __in BOOL fInstalled,
     __in DWORD cPackages
     );
-BAAPI UserExperienceOnDetectCompatibleMsiPackage(
-    __in BURN_USER_EXPERIENCE* pUserExperience,
-    __in_z LPCWSTR wzPackageId,
-    __in_z LPCWSTR wzCompatiblePackageId,
-    __in VERUTIL_VERSION* pCompatiblePackageVersion
-    );
 BAAPI UserExperienceOnDetectComplete(
     __in BURN_USER_EXPERIENCE* pUserExperience,
     __in HRESULT hrStatus
@@ -354,23 +348,6 @@ BAAPI UserExperienceOnPlanBegin(
     __in BURN_USER_EXPERIENCE* pUserExperience,
     __in DWORD cPackages
     );
-BAAPI UserExperienceOnPlanCompatibleMsiPackageBegin(
-    __in BURN_USER_EXPERIENCE* pUserExperience,
-    __in_z LPCWSTR wzPackageId,
-    __in_z LPCWSTR wzCompatiblePackageId,
-    __in VERUTIL_VERSION* pCompatiblePackageVersion,
-    __inout BOOTSTRAPPER_REQUEST_STATE* pRequestedState
-    );
-BAAPI UserExperienceOnPlanCompatibleMsiPackageComplete(
-    __in BURN_USER_EXPERIENCE* pUserExperience,
-    __in_z LPCWSTR wzPackageId,
-    __in_z LPCWSTR wzCompatiblePackageId,
-    __in HRESULT hrStatus,
-    __in BOOTSTRAPPER_PACKAGE_STATE state,
-    __in BOOTSTRAPPER_REQUEST_STATE requested,
-    __in BOOTSTRAPPER_ACTION_STATE execute,
-    __in BOOTSTRAPPER_ACTION_STATE rollback
-    );
 BAAPI UserExperienceOnPlanComplete(
     __in BURN_USER_EXPERIENCE* pUserExperience,
     __in HRESULT hrStatus