diff --git a/dlls/qedit/tests/timeline.c b/dlls/qedit/tests/timeline.c
index ecb42232acc..ca000632cd3 100644
--- a/dlls/qedit/tests/timeline.c
+++ b/dlls/qedit/tests/timeline.c
@@ -82,6 +82,15 @@ static void test_timeline(void)
     hr = IAMTimelineObj_GetTimelineType(obj, &type);
     ok(hr == S_OK, "GetTimelineType failed: %08x\n", hr);
     ok(type == TIMELINE_MAJOR_TYPE_COMPOSITE, "Expected TIMELINE_MAJOR_TYPE_COMPOSITE got %d\n", type);
+
+    for (type = 0; type < 256; type++)
+    {
+        hr = IAMTimelineObj_SetTimelineType(obj, type);
+        if (type == TIMELINE_MAJOR_TYPE_COMPOSITE)
+            ok(hr == S_OK, "SetTimelineType failed: %08x\n", hr);
+        else
+            ok(hr == E_INVALIDARG, "Expected E_INVALIDARG got %08x\n", hr);
+    }
 }
 
 START_TEST(timeline)
diff --git a/dlls/qedit/timeline.c b/dlls/qedit/timeline.c
index 0ecb1b511fe..a2552d21abc 100644
--- a/dlls/qedit/timeline.c
+++ b/dlls/qedit/timeline.c
@@ -602,9 +602,11 @@ static HRESULT WINAPI TimelineObj_GetTimelineType(IAMTimelineObj *iface, TIMELIN
 
 static HRESULT WINAPI TimelineObj_SetTimelineType(IAMTimelineObj *iface, TIMELINE_MAJOR_TYPE type)
 {
+    /* MSDN says that this function is "not supported" */
     TimelineObjImpl *This = impl_from_IAMTimelineObj(iface);
-    FIXME("(%p)->(%d): not implemented!\n", This, type);
-    return E_NOTIMPL;
+    TRACE("(%p)->(%d)\n", This, type);
+    if (type != This->timeline_type) return E_INVALIDARG;
+    return S_OK;
 }
 
 static HRESULT WINAPI TimelineObj_GetUserID(IAMTimelineObj *iface, LONG *id)