I have just started having the strangest problem. The code ends up boiling
down to the following (it is more contorted than it appears here):

SetProp(GetDesktopWindow(),"MyData",(HANDLE)someda ta);

This fails with an access denied report from GetLastError(). The thing is
this code has worked forever on every version of Windows (3.1 95, 98, NT4)
thus far. Stranger yet, it works on some versions of XP. In fact, it was
working just Wednesday with a clean install of XP Pro SP1 with the hot fixes
applied. I wiped the machine and reinstalled everything yesterday (but
without the automatic updates applied) and now it is not working
(Administrator login, any login).

The question is, is this a bug or is this the way that Windows is supposed
to work (and of so, when did this happen)?

I can rewrite things to get around this but it is the result of a framework
class and will be a brutal pain.

Regards,
Tom