The following Registry modification has solved this issue for me. Solid solution.
Copied from: Pavil Sojak (He should get credit for reposting this) and originally from: Posted by Anand Venkatachalapathy (trickyponywindows.blogspot.com/2010/10/outlook-2010-sync-issues-folder-is-full.html)
you can disable the logging for those, see google for "trickyponywindows" "outlook-2010-sync-issues-folder-is-full" (sorry this forum does not allow me to add links).
Key: HKEY_CURRENT_USER\ Software\Microsoft\Office\14.0\Outlook\Options
0 = Never save Modification Resolution logs
1 = Always save Modification Resolution logs
2 = Save Modification Resolution logs when a "critical conflict" occurs
<This is the new Default behavior when the EnableConflictLogging dword does not exist.>