We've got about 50 users plugged into the mobility server, it's been up for about 2 weeks now.
Every single day I get at least 2 users with a 0x80820001 activesync error (which googles out to be something about a bad contact - but we have verified that it can also be caused by a bad calendar entry as well).

Generally, unchecking Calendar & Contacts inside Activesync, letting the phone delete them, then re-downloading from the Mobility server will fix the user... for a few days. In cases where that won't fix, we have to remove the Activesync server entry from the phone & do a re-init on the user on the Mobility server in the Groupwise Connector, then re-connect to the server on the phone after that is done.

Some of these issues do appear to be caused by bad contacts (generally entries with same name in multiple books) in Groupwise, and I have the users clean those out and it works fine for a while. The strange thing is that the initial sync will go fine, and it will continue to sync just fine for a day or two before finally blowing up.

The other thing that seems to cause it is adding contacts on the phone. Something you kind of want your users to be able to do....

Anyone else had this issue at this volume? Found a fix?