diff --git a/dlls/quartz/tests/filtergraph.c b/dlls/quartz/tests/filtergraph.c
index 53b1f4fd3ed..4a1ce50d587 100644
--- a/dlls/quartz/tests/filtergraph.c
+++ b/dlls/quartz/tests/filtergraph.c
@@ -72,6 +72,7 @@ static void releasefiltergraph()
 
 START_TEST(filtergraph)
 {
+    CoInitialize(NULL);
     createfiltergraph();
 #if 0
     renderfile();