Actually moving this to the proper place.
diff --git a/vsprojects/vcxproj/grpc_unsecure/grpc_unsecure.vcxproj.filters b/vsprojects/vcxproj/grpc_unsecure/grpc_unsecure.vcxproj.filters
index 4f8a77d..738137d 100644
--- a/vsprojects/vcxproj/grpc_unsecure/grpc_unsecure.vcxproj.filters
+++ b/vsprojects/vcxproj/grpc_unsecure/grpc_unsecure.vcxproj.filters
@@ -391,6 +391,9 @@
     <ClCompile Include="$(SolutionDir)\..\src\core\census\operation.c">
       <Filter>src\core\census</Filter>
     </ClCompile>
+    <ClCompile Include="$(SolutionDir)\..\src\core\census\placeholders.c">
+      <Filter>src\core\census</Filter>
+    </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\src\core\census\tag_set.c">
       <Filter>src\core\census</Filter>
     </ClCompile>