1 files changed, 3 insertions, 0 deletions

diff --git a/src/WixToolset.Core/ExtensibilityServices/PreprocessHelper.cs b/src/WixToolset.Core/ExtensibilityServices/PreprocessHelper.cs
index bdf11879..e84bb001 100644
--- a/src/WixToolset.Core/ExtensibilityServices/PreprocessHelper.cs
+++ b/src/WixToolset.Core/ExtensibilityServices/PreprocessHelper.cs
@@ -244,6 +244,9 @@ namespace WixToolset.Core.ExtensibilityServices
                                 case Platform.ARM:
                                     return "arm";
 
+                                case Platform.ARM64:
+                                    return "arm64";
+
                                 default:
                                     throw new ArgumentException("Unknown platform enumeration '{0}' encountered.", context.Platform.ToString());
                             }