Issue: New mail items appear in the inbox for a moment then automatically move to the deleted items folder.
Cause: Non-resource mailbox is being automatically processed with resource mailbox settings.
Validation: Run the following Exchange power shell command (Exchange 2010).
Get-CalendarProcessing ALIAS |FL
RunspaceId : 3172fc10-…
AutomateProcessing : AutoAccept
AllowConflicts : False…
ForwardRequestsToDelegates : True
DeleteAttachments : True
DeleteComments : True
RemovePrivateProperty : True
DeleteSubject : True
AddOrganizerToSubject : True
DeleteNonCalendarItems : True
Fix: Normally these settings would be viewable and adjustable directly from the exchange management console, but it this case the resource settings are applied to a non-resource mailbox (it’s unclear how this happened). To resolve the issue you can run the command below, optionally you could modify the behavior if you wish to continue to use automated processing.
Set-CalendarProcessing ALIAS -AutomateProcessing:None