diff --git a/include/objidl.h b/include/objidl.h
index 1f3367384a2..285f0d8fba0 100644
--- a/include/objidl.h
+++ b/include/objidl.h
@@ -6260,7 +6260,7 @@ typedef struct _GDI_OBJECT {
 } GDI_OBJECT;
 
 typedef struct _userSTGMEDIUM {
-    struct _STGMEDIUM_UNION {
+    struct {
         DWORD tymed;
         union {
             wireHMETAFILEPICT hMetaFilePict;
diff --git a/include/objidl.idl b/include/objidl.idl
index d9202965960..bc87d4a74c2 100644
--- a/include/objidl.idl
+++ b/include/objidl.idl
@@ -1523,7 +1523,7 @@ interface IAdviseSink : IUnknown
   } GDI_OBJECT;
 
   typedef struct _userSTGMEDIUM {
-    union _STGMEDIUM_UNION switch(DWORD tymed) u {
+    union switch(DWORD tymed) u {
     case TYMED_NULL:     ;
     case TYMED_MFPICT:   wireHMETAFILEPICT hMetaFilePict;
     case TYMED_ENHMF:    wireHENHMETAFILE hHEnhMetaFile;