In CRM for Outlook, sometimes when you click the “track” or “set regarding” button, you will get an error telling you that the action cannot be completed during synchronization. I’ve noticed that sometimes I see this when tracking from the Outlook 2013 inbox view, rather than tracking from an individual email form.
If you see this error every time you track, it can be resolved by deleting the SQL CE database on the Client machine:
1. Close Outlook
2. Browse to C:\Users\<loggedinuser>\AppData\Roaming\Microsoft\MSCRM\Client
3. Delete the EmailCache.sdf and the OutlookSyncCache.sdf files
4. Browse to C:\Users\<loggedinuser>\AppData\Local\Microsoft\MSCRM\Client
5. Delete the CRMcache.sdf file and the GUIDFalse.sdf file <—the GUIDFalse.sdf file will be a long alphanumeric name
6. Re-launch Outlook and the files will get recreated.