After migrating from Exchange 2007 to Exchange 2013 CU9 when users send emails from Drafts folder of shared mailboxes using outlook 2007 they randomly get "Operation failed error".
Tried recreating outlook profile, removing reading permissions, disabled automapping but the issue keeps reoccurring.
There is no drop in connectivity at the time this happens. Outlook 2007 has got the latest patches. The issue does not accrue in outlook 2013 client.
