Add registry bitness to RegUtil and BUtil.

Fixes https://github.com/wixtoolset/issues/issues/6669.
Fixes https://github.com/wixtoolset/issues/issues/6670.

6 files changed, 219 insertions, 138 deletions

diff --git a/src/burn/engine/registration.cpp b/src/burn/engine/registration.cpp
index ffeb39d1..a5b061eb 100644
--- a/src/burn/engine/registration.cpp
+++ b/src/burn/engine/registration.cpp
@@ -1742,38 +1742,38 @@ static BOOL IsRegistryRebootPending()
     HKEY hk = NULL;
     BOOL fRebootPending = FALSE;
 
-    hr = RegKeyReadNumber(HKEY_LOCAL_MACHINE, L"SOFTWARE\\Microsoft\\ServerManager", L"CurrentRebootAttempts", TRUE, &dwValue);
+    hr = RegKeyReadNumber(HKEY_LOCAL_MACHINE, L"SOFTWARE\\Microsoft\\ServerManager", L"CurrentRebootAttempts", REG_KEY_DEFAULT, &dwValue);
     fRebootPending = SUCCEEDED(hr) && 0 < dwValue;
 
     if (!fRebootPending)
     {
-        hr = RegKeyReadNumber(HKEY_LOCAL_MACHINE, L"SOFTWARE\\Microsoft\\Updates", L"UpdateExeVolatile", TRUE, &dwValue);
+        hr = RegKeyReadNumber(HKEY_LOCAL_MACHINE, L"SOFTWARE\\Microsoft\\Updates", L"UpdateExeVolatile", REG_KEY_DEFAULT, &dwValue);
         fRebootPending = SUCCEEDED(hr) && 0 < dwValue;
 
         if (!fRebootPending)
         {
-            fRebootPending = RegValueExists(HKEY_LOCAL_MACHINE, L"SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Component Based Servicing\\RebootPending", NULL, TRUE);
+            fRebootPending = RegValueExists(HKEY_LOCAL_MACHINE, L"SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Component Based Servicing\\RebootPending", NULL, REG_KEY_DEFAULT);
 
             if (!fRebootPending)
             {
-                fRebootPending = RegValueExists(HKEY_LOCAL_MACHINE, L"SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Component Based Servicing\\RebootInProgress", NULL, TRUE);
+                fRebootPending = RegValueExists(HKEY_LOCAL_MACHINE, L"SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Component Based Servicing\\RebootInProgress", NULL, REG_KEY_DEFAULT);
 
                 if (!fRebootPending)
                 {
-                    hr = RegKeyReadNumber(HKEY_LOCAL_MACHINE, L"SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\WindowsUpdate\\Auto Update", L"AUState", TRUE, &dwValue);
+                    hr = RegKeyReadNumber(HKEY_LOCAL_MACHINE, L"SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\WindowsUpdate\\Auto Update", L"AUState", REG_KEY_DEFAULT, &dwValue);
                     fRebootPending = SUCCEEDED(hr) && 8 == dwValue;
 
                     if (!fRebootPending)
                     {
-                        fRebootPending = RegValueExists(HKEY_LOCAL_MACHINE, L"SYSTEM\\CurrentControlSet\\Control\\Session Manager", L"PendingFileRenameOperations", TRUE);
+                        fRebootPending = RegValueExists(HKEY_LOCAL_MACHINE, L"SYSTEM\\CurrentControlSet\\Control\\Session Manager", L"PendingFileRenameOperations", REG_KEY_DEFAULT);
 
                         if (!fRebootPending)
                         {
-                            fRebootPending = RegValueExists(HKEY_LOCAL_MACHINE, L"SYSTEM\\CurrentControlSet\\Control\\Session Manager", L"PendingFileRenameOperations2", TRUE);
+                            fRebootPending = RegValueExists(HKEY_LOCAL_MACHINE, L"SYSTEM\\CurrentControlSet\\Control\\Session Manager", L"PendingFileRenameOperations2", REG_KEY_DEFAULT);
 
                             if (!fRebootPending)
                             {
-                                hr = RegOpen(HKEY_LOCAL_MACHINE, L"SYSTEM\\CurrentControlSet\\Control\\Session Manager\\FileRenameOperations", KEY_READ | KEY_WOW64_64KEY, &hk);
+                                hr = RegOpenEx(HKEY_LOCAL_MACHINE, L"SYSTEM\\CurrentControlSet\\Control\\Session Manager\\FileRenameOperations", KEY_READ, REG_KEY_DEFAULT, &hk);
                                 if (SUCCEEDED(hr))
                                 {
                                     DWORD cSubKeys = 0;
diff --git a/src/libs/dutil/WixToolset.DUtil/butil.cpp b/src/libs/dutil/WixToolset.DUtil/butil.cpp
index 4c96dfc1..4262d573 100644
--- a/src/libs/dutil/WixToolset.DUtil/butil.cpp
+++ b/src/libs/dutil/WixToolset.DUtil/butil.cpp
@@ -55,6 +55,7 @@ static HRESULT OpenBundleKey(
     __in_z LPCWSTR wzBundleId,
     __in BUNDLE_INSTALL_CONTEXT context,
     __in_opt LPCWSTR wzSubKey,
+    __in REG_KEY_BITNESS kbKeyBitness,
     __inout HKEY* phKey
     );
 static HRESULT CopyStringToBuffer(
@@ -62,6 +63,14 @@ static HRESULT CopyStringToBuffer(
     __in_z_opt LPWSTR wzBuffer,
     __inout SIZE_T* pcchBuffer
     );
+static HRESULT DoBundleEnumRelatedBundle(
+    __in HKEY hkRoot,
+    __in REG_KEY_BITNESS kbKeyBitness,
+    __in_z LPCWSTR wzUpgradeCode,
+    __inout PDWORD pdwStartIndex,
+    __deref_out_z LPWSTR* psczBundleId
+    );
+
 
 DAPI_(HRESULT) BundleGetBundleInfo(
     __in_z LPCWSTR wzBundleId,
@@ -153,113 +162,26 @@ DAPI_(HRESULT) BundleEnumRelatedBundle(
 {
     HRESULT hr = S_OK;
     HKEY hkRoot = BUNDLE_INSTALL_CONTEXT_USER == context ? HKEY_CURRENT_USER : HKEY_LOCAL_MACHINE;
-    HKEY hkUninstall = NULL;
-    HKEY hkBundle = NULL;
-    LPWSTR sczUninstallSubKey = NULL;
-    LPWSTR sczUninstallSubKeyPath = NULL;
-    LPWSTR sczValue = NULL;
-    DWORD dwType = 0;
-
-    LPWSTR* rgsczBundleUpgradeCodes = NULL;
-    DWORD cBundleUpgradeCodes = 0;
-    BOOL fUpgradeCodeFound = FALSE;
 
     if (!wzUpgradeCode || !pdwStartIndex)
     {
         ButilExitOnFailure(hr = E_INVALIDARG, "An invalid parameter was passed to the function.");
     }
 
-    hr = RegOpen(hkRoot, BUNDLE_REGISTRATION_REGISTRY_UNINSTALL_KEY, KEY_READ, &hkUninstall);
-    ButilExitOnFailure(hr, "Failed to open bundle uninstall key path.");
-
-    for (DWORD dwIndex = *pdwStartIndex; !fUpgradeCodeFound; dwIndex++)
+    hr = DoBundleEnumRelatedBundle(hkRoot, REG_KEY_DEFAULT, wzUpgradeCode, pdwStartIndex, psczBundleId);
+    ButilExitOnFailure(hr, "Failed to enumerate default-bitness bundles.");
+    if (S_FALSE == hr)
     {
-        hr = RegKeyEnum(hkUninstall, dwIndex, &sczUninstallSubKey);
-        ButilExitOnFailure(hr, "Failed to enumerate bundle uninstall key path.");
-
-        hr = StrAllocFormatted(&sczUninstallSubKeyPath, L"%ls\\%ls", BUNDLE_REGISTRATION_REGISTRY_UNINSTALL_KEY, sczUninstallSubKey);
-        ButilExitOnFailure(hr, "Failed to allocate bundle uninstall key path.");
-        
-        hr = RegOpen(hkRoot, sczUninstallSubKeyPath, KEY_READ, &hkBundle);
-        ButilExitOnFailure(hr, "Failed to open uninstall key path.");
-
-        // If it's a bundle, it should have a BundleUpgradeCode value of type REG_SZ (old) or REG_MULTI_SZ
-        hr = RegGetType(hkBundle, BUNDLE_REGISTRATION_REGISTRY_BUNDLE_UPGRADE_CODE, &dwType);
-        if (FAILED(hr))
-        {
-            ReleaseRegKey(hkBundle);
-            ReleaseNullStr(sczUninstallSubKey);
-            ReleaseNullStr(sczUninstallSubKeyPath);
-            // Not a bundle
-            continue;
-        }
-
-        switch (dwType)
-        {
-            case REG_SZ:
-                hr = RegReadString(hkBundle, BUNDLE_REGISTRATION_REGISTRY_BUNDLE_UPGRADE_CODE, &sczValue);
-                ButilExitOnFailure(hr, "Failed to read BundleUpgradeCode string property.");
-
-                if (CSTR_EQUAL == ::CompareStringW(LOCALE_INVARIANT, NORM_IGNORECASE, sczValue, -1, wzUpgradeCode, -1))
-                {
-                    *pdwStartIndex = dwIndex;
-                    fUpgradeCodeFound = TRUE;
-                    break;
-                }
-
-                ReleaseNullStr(sczValue);
-
-                break;
-            case REG_MULTI_SZ:
-                hr = RegReadStringArray(hkBundle, BUNDLE_REGISTRATION_REGISTRY_BUNDLE_UPGRADE_CODE, &rgsczBundleUpgradeCodes, &cBundleUpgradeCodes);
-                ButilExitOnFailure(hr, "Failed to read BundleUpgradeCode  multi-string property.");
-
-                for (DWORD i = 0; i < cBundleUpgradeCodes; i++)
-                {
-                    LPWSTR wzBundleUpgradeCode = rgsczBundleUpgradeCodes[i];
-                    if (wzBundleUpgradeCode && *wzBundleUpgradeCode)
-                    {
-                        if (CSTR_EQUAL == ::CompareStringW(LOCALE_INVARIANT, NORM_IGNORECASE, wzBundleUpgradeCode, -1, wzUpgradeCode, -1))
-                        {
-                            *pdwStartIndex = dwIndex;
-                            fUpgradeCodeFound = TRUE;
-                            break;
-                        }
-                    }
-                }
-                ReleaseNullStrArray(rgsczBundleUpgradeCodes, cBundleUpgradeCodes);
-
-                break;
-
-            default:
-                ButilExitWithRootFailure(hr, E_NOTIMPL, "BundleUpgradeCode of type 0x%x not implemented.", dwType);
-        }
-
-        if (fUpgradeCodeFound)
-        {
-            if (psczBundleId)
-            {
-                *psczBundleId = sczUninstallSubKey;
-                sczUninstallSubKey = NULL;
-            }
-
-            break;
-        }
-
-        // Cleanup before next iteration
-        ReleaseRegKey(hkBundle);
-        ReleaseNullStr(sczUninstallSubKey);
-        ReleaseNullStr(sczUninstallSubKeyPath);
+#if defined(_WIN64)
+        hr = DoBundleEnumRelatedBundle(hkRoot, REG_KEY_32BIT, wzUpgradeCode, pdwStartIndex, psczBundleId);
+        ButilExitOnFailure(hr, "Failed to enumerate 32-bit bundles.");
+#else
+        hr = DoBundleEnumRelatedBundle(hkRoot, REG_KEY_64BIT, wzUpgradeCode, pdwStartIndex, psczBundleId);
+        ButilExitOnFailure(hr, "Failed to enumerate 64-bit bundles.");
+#endif
     }
 
 LExit:
-    ReleaseStr(sczValue);
-    ReleaseStr(sczUninstallSubKey);
-    ReleaseStr(sczUninstallSubKeyPath);
-    ReleaseRegKey(hkBundle);
-    ReleaseRegKey(hkUninstall);
-    ReleaseStrArray(rgsczBundleUpgradeCodes, cBundleUpgradeCodes);
-
     return hr;
 }
 
@@ -276,7 +198,7 @@ DAPI_(HRESULT) BundleEnumRelatedBundleFixed(
     size_t cchValue = 0;
 
     hr = BundleEnumRelatedBundle(wzUpgradeCode, context, pdwStartIndex, &sczValue);
-    if (SUCCEEDED(hr) && wzBundleId)
+    if (S_OK == hr && wzBundleId)
     {
         hr = ::StringCchLengthW(sczValue, STRSAFE_MAX_CCH, &cchValue);
         ButilExitOnRootFailure(hr, "Failed to calculate length of string.");
@@ -380,8 +302,9 @@ static HRESULT LocateAndQueryBundleValue(
 
     *pStatus = INTERNAL_BUNDLE_STATUS_SUCCESS;
 
-    if (FAILED(hr = OpenBundleKey(wzBundleId, BUNDLE_INSTALL_CONTEXT_MACHINE, wzSubKey, phKey)) &&
-        FAILED(hr = OpenBundleKey(wzBundleId, BUNDLE_INSTALL_CONTEXT_USER, wzSubKey, phKey)))
+    if (FAILED(hr = OpenBundleKey(wzBundleId, BUNDLE_INSTALL_CONTEXT_MACHINE, wzSubKey, REG_KEY_32BIT, phKey)) &&
+        FAILED(hr = OpenBundleKey(wzBundleId, BUNDLE_INSTALL_CONTEXT_MACHINE, wzSubKey, REG_KEY_64BIT, phKey)) &&
+        FAILED(hr = OpenBundleKey(wzBundleId, BUNDLE_INSTALL_CONTEXT_USER, wzSubKey, REG_KEY_DEFAULT, phKey)))
     {
         if (E_FILENOTFOUND == hr)
         {
@@ -413,6 +336,7 @@ static HRESULT OpenBundleKey(
     __in_z LPCWSTR wzBundleId,
     __in BUNDLE_INSTALL_CONTEXT context,
     __in_opt LPCWSTR wzSubKey,
+    __in REG_KEY_BITNESS kbKeyBitness,
     __inout HKEY* phKey
     )
 {
@@ -433,7 +357,7 @@ static HRESULT OpenBundleKey(
     }
     ButilExitOnFailure(hr, "Failed to allocate bundle uninstall key path.");
 
-    hr = RegOpen(hkRoot, sczKeypath, KEY_READ, phKey);
+    hr = RegOpenEx(hkRoot, sczKeypath, KEY_READ, kbKeyBitness, phKey);
     ButilExitOnFailure(hr, "Failed to open bundle uninstall key path.");
 
 LExit:
@@ -472,3 +396,116 @@ static HRESULT CopyStringToBuffer(
 
     return hr;
 }
+
+static HRESULT DoBundleEnumRelatedBundle(
+    __in HKEY hkRoot,
+    __in REG_KEY_BITNESS kbKeyBitness,
+    __in_z LPCWSTR wzUpgradeCode,
+    __inout PDWORD pdwStartIndex,
+    __deref_out_z LPWSTR* psczBundleId
+)
+{
+    HRESULT hr = S_OK;
+    BOOL fUpgradeCodeFound = FALSE;
+    HKEY hkUninstall = NULL;
+    HKEY hkBundle = NULL;
+    LPWSTR sczUninstallSubKey = NULL;
+    LPWSTR sczUninstallSubKeyPath = NULL;
+    LPWSTR sczValue = NULL;
+    DWORD dwType = 0;
+    LPWSTR* rgsczBundleUpgradeCodes = NULL;
+    DWORD cBundleUpgradeCodes = 0;
+
+    hr = RegOpenEx(hkRoot, BUNDLE_REGISTRATION_REGISTRY_UNINSTALL_KEY, KEY_READ, kbKeyBitness, &hkUninstall);
+    ButilExitOnFailure(hr, "Failed to open bundle uninstall key path.");
+
+    for (DWORD dwIndex = *pdwStartIndex; !fUpgradeCodeFound; dwIndex++)
+    {
+        hr = RegKeyEnum(hkUninstall, dwIndex, &sczUninstallSubKey);
+        ButilExitOnFailure(hr, "Failed to enumerate bundle uninstall key path.");
+
+        hr = StrAllocFormatted(&sczUninstallSubKeyPath, L"%ls\\%ls", BUNDLE_REGISTRATION_REGISTRY_UNINSTALL_KEY, sczUninstallSubKey);
+        ButilExitOnFailure(hr, "Failed to allocate bundle uninstall key path.");
+
+        hr = RegOpenEx(hkRoot, sczUninstallSubKeyPath, KEY_READ, kbKeyBitness, &hkBundle);
+        ButilExitOnFailure(hr, "Failed to open uninstall key path.");
+
+        // If it's a bundle, it should have a BundleUpgradeCode value of type REG_SZ (old) or REG_MULTI_SZ
+        hr = RegGetType(hkBundle, BUNDLE_REGISTRATION_REGISTRY_BUNDLE_UPGRADE_CODE, &dwType);
+        if (FAILED(hr))
+        {
+            ReleaseRegKey(hkBundle);
+            ReleaseNullStr(sczUninstallSubKey);
+            ReleaseNullStr(sczUninstallSubKeyPath);
+            // Not a bundle
+            continue;
+        }
+
+        switch (dwType)
+        {
+        case REG_SZ:
+            hr = RegReadString(hkBundle, BUNDLE_REGISTRATION_REGISTRY_BUNDLE_UPGRADE_CODE, &sczValue);
+            ButilExitOnFailure(hr, "Failed to read BundleUpgradeCode string property.");
+
+            if (CSTR_EQUAL == ::CompareStringW(LOCALE_INVARIANT, NORM_IGNORECASE, sczValue, -1, wzUpgradeCode, -1))
+            {
+                *pdwStartIndex = dwIndex;
+                fUpgradeCodeFound = TRUE;
+                break;
+            }
+
+            ReleaseNullStr(sczValue);
+
+            break;
+        case REG_MULTI_SZ:
+            hr = RegReadStringArray(hkBundle, BUNDLE_REGISTRATION_REGISTRY_BUNDLE_UPGRADE_CODE, &rgsczBundleUpgradeCodes, &cBundleUpgradeCodes);
+            ButilExitOnFailure(hr, "Failed to read BundleUpgradeCode multi-string property.");
+
+            for (DWORD i = 0; i < cBundleUpgradeCodes; i++)
+            {
+                LPWSTR wzBundleUpgradeCode = rgsczBundleUpgradeCodes[i];
+                if (wzBundleUpgradeCode && *wzBundleUpgradeCode)
+                {
+                    if (CSTR_EQUAL == ::CompareStringW(LOCALE_INVARIANT, NORM_IGNORECASE, wzBundleUpgradeCode, -1, wzUpgradeCode, -1))
+                    {
+                        *pdwStartIndex = dwIndex;
+                        fUpgradeCodeFound = TRUE;
+                        break;
+                    }
+                }
+            }
+            ReleaseNullStrArray(rgsczBundleUpgradeCodes, cBundleUpgradeCodes);
+
+            break;
+
+        default:
+            ButilExitWithRootFailure(hr, E_NOTIMPL, "BundleUpgradeCode of type 0x%x not implemented.", dwType);
+        }
+
+        if (fUpgradeCodeFound)
+        {
+            if (psczBundleId)
+            {
+                *psczBundleId = sczUninstallSubKey;
+                sczUninstallSubKey = NULL;
+            }
+
+            break;
+        }
+
+        // Cleanup before next iteration
+        ReleaseRegKey(hkBundle);
+        ReleaseNullStr(sczUninstallSubKey);
+        ReleaseNullStr(sczUninstallSubKeyPath);
+    }
+
+LExit:
+    ReleaseStr(sczValue);
+    ReleaseStr(sczUninstallSubKey);
+    ReleaseStr(sczUninstallSubKeyPath);
+    ReleaseRegKey(hkBundle);
+    ReleaseRegKey(hkUninstall);
+    ReleaseStrArray(rgsczBundleUpgradeCodes, cBundleUpgradeCodes);
+
+    return FAILED(hr) ? hr : fUpgradeCodeFound ? S_OK : S_FALSE;
+}
diff --git a/src/libs/dutil/WixToolset.DUtil/deputil.cpp b/src/libs/dutil/WixToolset.DUtil/deputil.cpp
index 2e6d6a6c..754365e9 100644
--- a/src/libs/dutil/WixToolset.DUtil/deputil.cpp
+++ b/src/libs/dutil/WixToolset.DUtil/deputil.cpp
@@ -337,7 +337,7 @@ DAPI_(HRESULT) DepRegisterDependency(
     DepExitOnFailure(hr, "Failed to allocate the registry key for dependency \"%ls\".", wzProviderKey);
 
     // Create the dependency key (or open it if it already exists).
-    hr = RegCreateEx(hkHive, sczKey, KEY_WRITE, FALSE, NULL, &hkKey, &fCreated);
+    hr = RegCreateEx(hkHive, sczKey, KEY_WRITE, REG_KEY_DEFAULT, FALSE, NULL, &hkKey, &fCreated);
     DepExitOnFailure(hr, "Failed to create the dependency registry key \"%ls\".", sczKey);
 
     // Set the id if it was provided.
@@ -417,14 +417,14 @@ DAPI_(HRESULT) DepRegisterDependent(
     DepExitOnFailure(hr, "Failed to allocate the registry key for dependency \"%ls\".", wzDependencyProviderKey);
 
     // Create the dependency key (or open it if it already exists).
-    hr = RegCreateEx(hkHive, sczDependencyKey, KEY_WRITE, FALSE, NULL, &hkDependencyKey, &fCreated);
+    hr = RegCreateEx(hkHive, sczDependencyKey, KEY_WRITE, REG_KEY_DEFAULT, FALSE, NULL, &hkDependencyKey, &fCreated);
     DepExitOnFailure(hr, "Failed to create the dependency registry key \"%ls\".", sczDependencyKey);
 
     // Create the subkey to register the dependent.
     hr = StrAllocFormatted(&sczKey, L"%ls\\%ls", vsczRegistryDependents, wzProviderKey);
     DepExitOnFailure(hr, "Failed to allocate dependent subkey \"%ls\" under dependency \"%ls\".", wzProviderKey, wzDependencyProviderKey);
 
-    hr = RegCreateEx(hkDependencyKey, sczKey, KEY_WRITE, FALSE, NULL, &hkKey, &fCreated);
+    hr = RegCreateEx(hkDependencyKey, sczKey, KEY_WRITE, REG_KEY_DEFAULT, FALSE, NULL, &hkKey, &fCreated);
     DepExitOnFailure(hr, "Failed to create the dependency subkey \"%ls\".", sczKey);
 
     // Set the minimum version if not NULL.
diff --git a/src/libs/dutil/WixToolset.DUtil/inc/butil.h b/src/libs/dutil/WixToolset.DUtil/inc/butil.h
index 0405be8b..3b316e66 100644
--- a/src/libs/dutil/WixToolset.DUtil/inc/butil.h
+++ b/src/libs/dutil/WixToolset.DUtil/inc/butil.h
@@ -64,6 +64,10 @@ BundleEnumRelatedBundle - Queries the bundle installation metadata for installs
 RETURNS:
     E_INVALIDARG
         An invalid parameter was passed to the function.
+    S_OK
+        Related bundle was found.
+    S_FALSE
+        Related bundle was not found.
 
     All other returns are unexpected returns from other dutil methods.
 ********************************************************************/
@@ -82,6 +86,10 @@ NOTE: lpBundleIdBuff is a buffer to receive the bundle GUID. This buffer must be
 RETURNS:
     E_INVALIDARG
         An invalid parameter was passed to the function.
+    S_OK
+        Related bundle was found.
+    S_FALSE
+        Related bundle was not found.
 
     All other returns are unexpected returns from other dutil methods.
 ********************************************************************/
diff --git a/src/libs/dutil/WixToolset.DUtil/inc/regutil.h b/src/libs/dutil/WixToolset.DUtil/inc/regutil.h
index ae47f75e..db8e0c5c 100644
--- a/src/libs/dutil/WixToolset.DUtil/inc/regutil.h
+++ b/src/libs/dutil/WixToolset.DUtil/inc/regutil.h
@@ -147,6 +147,7 @@ HRESULT DAPI RegCreateEx(
     __in HKEY hkRoot,
     __in_z LPCWSTR wzSubKey,
     __in DWORD dwAccess,
+    __in REG_KEY_BITNESS kbKeyBitness,
     __in BOOL fVolatile,
     __in_opt SECURITY_ATTRIBUTES* pSecurityAttributes,
     __out HKEY* phk,
@@ -162,7 +163,19 @@ HRESULT DAPI RegOpen(
     __in_z LPCWSTR wzSubKey,
     __in DWORD dwAccess,
     __out HKEY* phk
-    );
+);
+
+/********************************************************************
+ RegOpenEx - opens a registry key.
+
+*********************************************************************/
+HRESULT DAPI RegOpenEx(
+    __in HKEY hkRoot,
+    __in_z LPCWSTR wzSubKey,
+    __in DWORD dwAccess,
+    __in REG_KEY_BITNESS kbKeyBitness,
+    __out HKEY* phk
+);
 
 /********************************************************************
  RegDelete - deletes a registry key (and optionally it's whole tree).
@@ -379,7 +392,7 @@ HRESULT DAPI RegKeyReadNumber(
     __in HKEY hk,
     __in_z LPCWSTR wzSubKey,
     __in_z_opt LPCWSTR wzName,
-    __in BOOL f64Bit,
+    __in REG_KEY_BITNESS kbKeyBitness,
     __out DWORD* pdwValue
     );
 
@@ -392,7 +405,7 @@ BOOL DAPI RegValueExists(
     __in HKEY hk,
     __in_z LPCWSTR wzSubKey,
     __in_z_opt LPCWSTR wzName,
-    __in BOOL f64Bit
+    __in REG_KEY_BITNESS kbKeyBitness
     );
 
 #ifdef __cplusplus
diff --git a/src/libs/dutil/WixToolset.DUtil/regutil.cpp b/src/libs/dutil/WixToolset.DUtil/regutil.cpp
index 57093f97..f4719466 100644
--- a/src/libs/dutil/WixToolset.DUtil/regutil.cpp
+++ b/src/libs/dutil/WixToolset.DUtil/regutil.cpp
@@ -32,6 +32,9 @@ static PFN_REGDELETEVALUEW vpfnRegDeleteValueW = ::RegDeleteValueW;
 static HMODULE vhAdvApi32Dll = NULL;
 static BOOL vfRegInitialized = FALSE;
 
+static REGSAM TranslateKeyBitness(
+    __in REG_KEY_BITNESS kbKeyBitness
+);
 static HRESULT WriteStringToRegistry(
     __in HKEY hk,
     __in_z_opt LPCWSTR wzName,
@@ -121,6 +124,7 @@ DAPI_(HRESULT) RegCreateEx(
     __in HKEY hkRoot,
     __in_z LPCWSTR wzSubKey,
     __in DWORD dwAccess,
+    __in REG_KEY_BITNESS kbKeyBitness,
     __in BOOL fVolatile,
     __in_opt SECURITY_ATTRIBUTES* pSecurityAttributes,
     __out HKEY* phk,
@@ -131,7 +135,8 @@ DAPI_(HRESULT) RegCreateEx(
     DWORD er = ERROR_SUCCESS;
     DWORD dwDisposition;
 
-    er = vpfnRegCreateKeyExW(hkRoot, wzSubKey, 0, NULL, fVolatile ? REG_OPTION_VOLATILE : REG_OPTION_NON_VOLATILE, dwAccess, pSecurityAttributes, phk, &dwDisposition);
+    REGSAM samDesired = TranslateKeyBitness(kbKeyBitness);
+    er = vpfnRegCreateKeyExW(hkRoot, wzSubKey, 0, NULL, fVolatile ? REG_OPTION_VOLATILE : REG_OPTION_NON_VOLATILE, dwAccess | samDesired, pSecurityAttributes, phk, &dwDisposition);
     RegExitOnWin32Error(er, hr, "Failed to create registry key.");
 
     if (pfCreated)
@@ -149,12 +154,25 @@ DAPI_(HRESULT) RegOpen(
     __in_z LPCWSTR wzSubKey,
     __in DWORD dwAccess,
     __out HKEY* phk
-    )
+)
+{
+    return RegOpenEx(hkRoot, wzSubKey, dwAccess, REG_KEY_DEFAULT, phk);
+}
+
+
+DAPI_(HRESULT) RegOpenEx(
+    __in HKEY hkRoot,
+    __in_z LPCWSTR wzSubKey,
+    __in DWORD dwAccess,
+    __in REG_KEY_BITNESS kbKeyBitness,
+    __out HKEY* phk
+)
 {
     HRESULT hr = S_OK;
     DWORD er = ERROR_SUCCESS;
 
-    er = vpfnRegOpenKeyExW(hkRoot, wzSubKey, 0, dwAccess, phk);
+    REGSAM samDesired = TranslateKeyBitness(kbKeyBitness);
+    er = vpfnRegOpenKeyExW(hkRoot, wzSubKey, 0, dwAccess | samDesired, phk);
     if (E_FILENOTFOUND == HRESULT_FROM_WIN32(er))
     {
         ExitFunction1(hr = E_FILENOTFOUND);
@@ -178,7 +196,6 @@ DAPI_(HRESULT) RegDelete(
     LPWSTR pszEnumeratedSubKey = NULL;
     LPWSTR pszRecursiveSubKey = NULL;
     HKEY hkKey = NULL;
-    REGSAM samDesired = 0;
 
     if (!vfRegInitialized && REG_KEY_DEFAULT != kbKeyBitness)
     {
@@ -186,22 +203,9 @@ DAPI_(HRESULT) RegDelete(
         RegExitOnFailure(hr, "RegInitialize must be called first in order to RegDelete() a key with non-default bit attributes!");
     }
 
-    switch (kbKeyBitness)
-    {
-    case REG_KEY_32BIT:
-        samDesired = KEY_WOW64_32KEY;
-        break;
-    case REG_KEY_64BIT:
-        samDesired = KEY_WOW64_64KEY;
-        break;
-    case REG_KEY_DEFAULT:
-        // Nothing to do
-        break;
-    }
-
     if (fDeleteTree)
     {
-        hr = RegOpen(hkRoot, wzSubKey, KEY_READ | samDesired, &hkKey);
+        hr = RegOpenEx(hkRoot, wzSubKey, KEY_READ, kbKeyBitness, &hkKey);
         if (E_FILENOTFOUND == hr)
         {
             ExitFunction1(hr = S_OK);
@@ -225,6 +229,7 @@ DAPI_(HRESULT) RegDelete(
 
     if (NULL != vpfnRegDeleteKeyExW)
     {
+        REGSAM samDesired = TranslateKeyBitness(kbKeyBitness);
         er = vpfnRegDeleteKeyExW(hkRoot, wzSubKey, samDesired, 0);
         if (E_FILENOTFOUND == HRESULT_FROM_WIN32(er))
         {
@@ -250,7 +255,6 @@ LExit:
     return hr;
 }
 
-
 DAPI_(HRESULT) RegKeyEnum(
     __in HKEY hk,
     __in DWORD dwIndex,
@@ -889,14 +893,14 @@ DAPI_(HRESULT) RegKeyReadNumber(
     __in HKEY hk,
     __in_z LPCWSTR wzSubKey,
     __in_z_opt LPCWSTR wzName,
-    __in BOOL f64Bit,
+    __in REG_KEY_BITNESS kbKeyBitness,
     __out DWORD* pdwValue
     )
 {
     HRESULT hr = S_OK;
     HKEY hkKey = NULL;
 
-    hr = RegOpen(hk, wzSubKey, KEY_READ | f64Bit ? KEY_WOW64_64KEY : 0, &hkKey);
+    hr = RegOpenEx(hk, wzSubKey, KEY_READ, kbKeyBitness, &hkKey);
     RegExitOnFailure(hr, "Failed to open key: %ls", wzSubKey);
 
     hr = RegReadNumber(hkKey, wzName, pdwValue);
@@ -917,14 +921,14 @@ DAPI_(BOOL) RegValueExists(
     __in HKEY hk,
     __in_z LPCWSTR wzSubKey,
     __in_z_opt LPCWSTR wzName,
-    __in BOOL f64Bit
+    __in REG_KEY_BITNESS kbKeyBitness
     )
 {
     HRESULT hr = S_OK;
     HKEY hkKey = NULL;
     DWORD dwType = 0;
 
-    hr = RegOpen(hk, wzSubKey, KEY_READ | f64Bit ? KEY_WOW64_64KEY : 0, &hkKey);
+    hr = RegOpenEx(hk, wzSubKey, KEY_READ, kbKeyBitness, &hkKey);
     RegExitOnFailure(hr, "Failed to open key: %ls", wzSubKey);
 
     hr = RegGetType(hkKey, wzName, &dwType);
@@ -936,6 +940,25 @@ LExit:
     return SUCCEEDED(hr);
 }
 
+static REGSAM TranslateKeyBitness(
+    __in REG_KEY_BITNESS kbKeyBitness
+    )
+{
+    switch (kbKeyBitness)
+    {
+    case REG_KEY_32BIT:
+        return KEY_WOW64_32KEY;
+        break;
+    case REG_KEY_64BIT:
+        return KEY_WOW64_64KEY;
+        break;
+    case REG_KEY_DEFAULT:
+    default:
+        return 0;
+        break;
+    }
+}
+
 static HRESULT WriteStringToRegistry(
     __in HKEY hk,
     __in_z_opt LPCWSTR wzName,