Index: /trunk/src/VBox/Additions/common/VBoxService/VBoxServiceAutoMount.cpp
===================================================================
--- /trunk/src/VBox/Additions/common/VBoxService/VBoxServiceAutoMount.cpp	(revision 33846)
+++ /trunk/src/VBox/Additions/common/VBoxService/VBoxServiceAutoMount.cpp	(revision 33847)
@@ -158,5 +158,5 @@
     if (RT_SUCCESS(rc))
     {
-        rc = RTPathSetOwnerEx(pszMountPoint, -1 /* Owner, unchanged */, pOpts->gid, RTPATH_F_ON_LINK);
+        rc = RTPathSetOwnerEx(pszMountPoint, ~0 /* Owner, unchanged */, pOpts->gid, RTPATH_F_ON_LINK);
         if (RT_SUCCESS(rc))
         {