diff --git a/dlls/dmloader/loader.c b/dlls/dmloader/loader.c
index 4b76f325f66..e44d2b9fa7c 100644
--- a/dlls/dmloader/loader.c
+++ b/dlls/dmloader/loader.c
@@ -111,25 +111,6 @@ static HRESULT DMUSIC_CopyDescriptor(DMUS_OBJECTDESC *pDst, DMUS_OBJECTDESC *pSr
 	return S_OK;
 }
 
-
-static BOOL DMUSIC_IsValidLoadableClass (REFCLSID pClassID) {
-	if (IsEqualCLSID(pClassID, &CLSID_DirectMusicAudioPathConfig) ||
-		IsEqualCLSID(pClassID, &CLSID_DirectMusicBand) ||
-		IsEqualCLSID(pClassID, &CLSID_DirectMusicContainer) ||
-		IsEqualCLSID(pClassID, &CLSID_DirectMusicCollection) ||
-		IsEqualCLSID(pClassID, &CLSID_DirectMusicChordMap) ||
-		IsEqualCLSID(pClassID, &CLSID_DirectMusicSegment) ||
-		IsEqualCLSID(pClassID, &CLSID_DirectMusicScript) ||
-		IsEqualCLSID(pClassID, &CLSID_DirectMusicSong) ||
-		IsEqualCLSID(pClassID, &CLSID_DirectMusicStyle) ||
-		IsEqualCLSID(pClassID, &CLSID_DirectMusicGraph) ||
-		IsEqualCLSID(pClassID, &CLSID_DirectSoundWave) ||
-		IsEqualCLSID(pClassID, &GUID_DirectMusicAllTypes))
-		return TRUE;
-	else
-		return FALSE;
-}
-
 /*****************************************************************************
  * IDirectMusicLoaderImpl implementation
  */
@@ -599,7 +580,7 @@ static HRESULT WINAPI IDirectMusicLoaderImpl_ScanDirectory(IDirectMusicLoader8 *
 	HRESULT result;
         TRACE("(%p, %s, %s, %s)\n", This, debugstr_dmguid(rguidClass), debugstr_w(pwzFileExtension),
                         debugstr_w(pwzScanFileName));
-	if (IsEqualGUID (rguidClass, &GUID_DirectMusicAllTypes) || !DMUSIC_IsValidLoadableClass(rguidClass)) {
+        if (index_from_class(rguidClass) <= 0) {
 		ERR(": rguidClass invalid CLSID\n");
 		return REGDB_E_CLASSNOTREG;
 	}
diff --git a/dlls/dmloader/tests/loader.c b/dlls/dmloader/tests/loader.c
index 5d5cff46887..ff084b6e4b7 100644
--- a/dlls/dmloader/tests/loader.c
+++ b/dlls/dmloader/tests/loader.c
@@ -87,6 +87,8 @@ static void test_directory(void)
         IDirectMusicLoader_SetSearchDirectory(loader, NULL, path, 0); /* Crashes on Windows */
     hr = IDirectMusicLoader_SetSearchDirectory(loader, &IID_IDirectMusicLoader8, path, 0);
     ok(hr == S_OK, "SetSearchDirectory failed with %#x\n", hr);
+    hr = IDirectMusicLoader_ScanDirectory(loader, &GUID_DirectMusicAllTypes, con, NULL);
+    ok(hr == REGDB_E_CLASSNOTREG, "ScanDirectory failed, received %#x\n", hr);
 
     /* NULL extension is not an error */
     hr = IDirectMusicLoader_ScanDirectory(loader, &CLSID_DirectSoundWave, NULL, NULL);