>>I did get a MS update last week- could be the problem.

We just moved an app back to Windows fat client that had been a browser app for well over 15 years, because of this sort of thing. The potential nightmare scenario was an automatically applied patch or security fix breaking our browser app irreversibly without warning, leaving us with desperate customers and a browser app that cannot be remedied by us, only by tinkering with/rolling back patches. Planning began when an important client tightened browser security and it took days to figure out why our ActiveX that interfaces to another product, now was blocked. The remedy involved complicated machinations wrt security with local experts insisting that MS has a rolling program to close holes that can be abused, so the solution is to stand by ready to fix sudden breakages as they occur. We consider that to be bad customer service for customers who have trusted us to provide rock solid apps for over a quarter of a century in some cases, so we went a different direction.