diff --git a/eng/test-rebuild.ps1 b/eng/test-rebuild.ps1
index 68eeda7dfd6c9..ed0e3aa5c0273 100644
--- a/eng/test-rebuild.ps1
+++ b/eng/test-rebuild.ps1
@@ -67,7 +67,8 @@ try {
 
   # Semantic Search reference assemblies can't be reconstructed from source.
   # The assemblies are not marked with ReferenceAssemblyAttribute attribute.
-  " --exclude net9.0\GeneratedRefAssemblies\Microsoft.CodeAnalysis.dll" +
+  " --exclude net8.0\GeneratedRefAssemblies\Microsoft.CodeAnalysis.dll" +
+  " --exclude net8.0\GeneratedRefAssemblies\Microsoft.CodeAnalysis.CSharp.dll" +
 
   " --debugPath `"$ArtifactsDir/BuildValidator`"" +
   " --sourcePath `"$RepoRoot/`"" +