http://bugs.winehq.org/show_bug.cgi?id=21938
--- Comment #11 from Henri Verbeet hverbeet@gmail.com 2010-03-06 12:59:57 --- I don't suppose there's any helpful information in the event log?
It would help a lot if you could narrow it down to a specific test, but I understand that may not be reasonably possible. As a guess, since it seems specific to secured networks, I'd be suspicious of any cryptography / certificate related tests, like e.g. the crypt32 ones.