In Windows XP, applications are restricted from modifying the system menu. Instead, each application gets a separate copy ...

In Windows XP, applications are restricted from modifying the system menu. Instead, each application gets a separate copy of the system menu. Some applications may try to get a handle to the real system menu and attempt to modify it. This compatibility fix makes the AppendMenu API return TRUE all the time, since there is no way to tell if an HMENU is the handle to the real system menu or simply a handle to the local copy of the system menu.