I have a small windows GUI program based on win32eventreactor and win32gui (from pywin32).  It pops up a small dialog, gathers some information from the user, then makes an SSL connection to a server and sends the information.

This program has been running on over 40 different systems (XP, Vista, Windows Server, Windows 7) for a while now, without any problems.  Today I had one potential customer tell me that he could enter text in the first text field on the dialog, but could not change move focus to the next text field, or any other control in the dialog, either by tabbing or clicking.  I've never seen anything like this.

I don't know if this is a twisted problem or a win32gui problem, or a problem in my code and unfortunately I can't get any more information from the customer.

Has anyone seen anything like this before?  Any ideas where to start?

I'm running Twisted 2.5.0 on python 2.5.1.  I'm aware these are old, but I've never had any problems with them before.  Upgrading is on my todo list.