After normal function for over a year, we began to experience a problem in Excel 2010 running on Windows 7. When we try to format cells or change the font, we see a freezing or crashing behavior. Freezing is accompanied with a (not responding) message. It will resolve in 30 seconds or so. The problem is reliably reproduced the first time we format cells after opening Excel the first time for the day. After which, the freezing/crash is sporadic. Uninstalling and reinstalling Office has not helped.
We still see the problem after disabling addins. We do not see the problem in Safe Mode.