Hello,
I've had this issue for years with WSS 3.0 calendars and Outlook 2007/2010 and now I'm starting to get calls about this with SharePoint 2010 SP1 calendars and Outlook 2010 SP1 clients. I thought moving from WSS to 2010 Enterprise had solved this, but unfortunately not.
The issue I am facing is this:
I have Calendars set up in SharePoint 2010 and connect them to Outlook 2007/2010 clients. They have proper permissions, initially can sync properly, and life is good. Then randomly, months down the road they enter a new appointment into these SP calendars (from Outlook) and assume everything is working as it should as they don't receive and errors when Outlook does it's auto send/receive. Eventually others in the same department who use the same SP calendar cannot see the appointments the first person had made. Then appointments get double-booked and chaos roams the halls and we (IT Dept) get calls. I've found that by going to Properties > General Tab of the SP Calendar in Outlook, I can then 'Clear Offline Items' and that particular workstation is fine until it happens again. They, of course, lose all appointments they've booked since the issue started.
How can I prevent Outlook from even keeping offline items for SharePoint lists? Maybe there's a documented solution I'm not finding? I've even called Microsoft Paid Support and they had no solution as there were no log files generated for this. As of today, I've found a Group Policy that will enable logging for Outlook/SharePoint syncs. Maybe this can give us some insight, but it seems to be tied to the Offline Items Outlook creates. Microsoft Support and I determined this was an Outlook issue, not a SharePoint. When the client is having this issue, users can still use the web page for SharePoint calendar list and see the actual updated list. If they add an item from the web, the problem workstation cannot download that new item.
Maybe I have a Group Policy that's causing this issue? Not sure? It's affecting various departments, on different subnets, and different switches so it's not even isolated.
Also, I have not found a way to recreate this problem. I always come back to this every few months when someone calls again.
Any help would be very much appreciated!
Rory
Rory Schmitz
