WH_CALLWNDPROC hooks are called from the context of the process that calls SendMessage(), not the one that receives the message. As long as a message is sent by the same process as the one you're wanting to subclass the window in, it should be OK. These will work, but these hook functions are called for every message sent to every window. They substantially slow down the system and are not recommended unless absolutely necessary. Ryan Being little and getting pushed around by big guys all my life I guess I compensate by pushing electrons and holes around. What a bully I am, but I do enjoy making subatomic particles hop at my bidding - Roger Wright (2nd April 2003, The Lounge)
Punctuality is only a virtue for those who aren't smart enough to think of good excuses for being late - John Nichol "Point Of Impact"