diff --git a/src/Microsoft.DotNet.Wpf/src/PresentationBuildTasks/Microsoft/Build/Tasks/Windows/GenerateTemporaryTargetAssembly.cs b/src/Microsoft.DotNet.Wpf/src/PresentationBuildTasks/Microsoft/Build/Tasks/Windows/GenerateTemporaryTargetAssembly.cs
index 3cb7ac44c50..9138b45eca4 100644
--- a/src/Microsoft.DotNet.Wpf/src/PresentationBuildTasks/Microsoft/Build/Tasks/Windows/GenerateTemporaryTargetAssembly.cs
+++ b/src/Microsoft.DotNet.Wpf/src/PresentationBuildTasks/Microsoft/Build/Tasks/Windows/GenerateTemporaryTargetAssembly.cs
@@ -179,7 +179,7 @@ private bool ExecuteLegacyGenerateTemporaryTargetAssembly()
 
                 globalProperties[assemblyNamePropertyName] = AssemblyName;
                 globalProperties[targetAssemblyProjectNamePropertyName] = currentProjectName;
-
+                globalProperties["EmbedUntrackedSources"] = "false";
                 Dictionary<string, ITaskItem[]> targetOutputs = new Dictionary<string, ITaskItem[]>();
                 retValue = BuildEngine.BuildProjectFile(tempProj, new string[] { CompileTargetName }, globalProperties, targetOutputs);