I just tried to clean up my Deleted Items folder in Outlook 2013 and got the two following errors:
Cannot delete this folder. Right-click the folder, and then click Properties to check your permissions for this folder. See the folder owner or your administrator to change your permissions. Outlook is synchronizing local changes made to items in this folder. You cannot remove this folder until the synchronization with the server is complete.
“Outlook is synchronizing local changes made to items in this folder. You cannot remove this folder until the synchronization with the server is complete.”
I messed around with the Properties pane for a bit but nothing worked.
OWA to the rescue. OWA = Outlook Web Access – it apparently doesn’t have all the complex sync logic that the Windows app does. I went to OWA, right clicked on Deleted Items, clicked empty and it worked.
Workaround: Whenever you have issues like this in the Outlook client, go to OWA and give it a try. Poor excuse for a workaround, but I don’t have time to figure out why Outlook is complaining.