Win95 shutdown messages is ???

I've got a small D3 app that checks for mail in the background...does
it's miniscule job down in the taskbar. When the user wants to exit
they have to close this app first or Win95 won't exit. I think I want
to trap for a WM_??? but can't seem to find what I'm looking for in
the winapi help (not that it sucks or anything<g>). Anyway, a pointer
would be much appreciated, some sample source worshipped. tia,

Grant Carpenter
grant@t r a n s p e r.com