Exchange no longer working after upgrading to Froyo I have a HTC Desire that was on 2.1 and worked perfectly with my works exchange server.
But since upgrading to 2.2 I cannot get it to work at all. There are no errors it just synchs forever.

Any suggestions?
It looks like there is an issue with the Exchange Server certificates and Froyo. I have found a few others with the same issue:


Exchange 2007 doesn't work after ota 2.2 update
Android 2.2, FRF91 now Active-sync is unable to connect to server, all was fine on Android 2.1


Those links have several workarounds that might solve your problem as long as you can get your IT team to help figure out what is going on. 

I have seen several people mention the the Touchdown (appbrain link) app is not having any problems. Touchdown is an alternative to the built-in Exchange sync. It might be the easiest solution for you - though it is a paid app - $19.99 as of right now.

QR Code for the app market: