In early August 2011, the Windows SE team released the following Knowledge Base (KB) article and accompanying software hotfix regarding an issue in Windows Server 2008 R2 failover clusters: KB2550886 - A transient communication failure causes a Windows...

Mailbox cleanup could not completely remove the mailbox for user XXXXXXX following mailbox removal. Encountered error 0xfffffae8. Should this message continue to persist for the same mailbox, it may be indicative of a problem that requires further investigation...