Just recently I’ve got this weird issue.
Mailbox got stuck. I was able to remove emails from inbox folder and subfolders, even from the Recovery Items folder BUT… not from the deleted items folder.
The behaviour was weird – I was removing some emails and they were reappear after some time, same with MFCMAPI – was clicking hard delete and these bastards didn’t even move.
I was even not able to move the mailbox as it was telling me that mailbox exceeded the quota – I knew it – well, let me remove these emails then!!!
The reason for that appeared very trivial, I’ve been mentioning about this mechanism here: https://paweljarosz.wordpress.com/2015/09/08/singleitemrecovery-in-exchange-2013-recovering-emails-from-purges-folder-with-search-mailbox-cmdlet/
Mailbox had litigation hold enabled and the “Purges” folder on the mailbox got filled up to 100GB. I thouhgt that these emails will be moved to archive but somehow these were still in the mailbox space causign the issue.
Removing the litigation hold allowed to finally delete the emails from deleted items.
Just as a reminder to check what is the size of the “Purges” folder run:
Get-MailboxFolderStatistics -Identity “<mailbox_name>” -FolderScope RecoverableItems -IncludeAnalysis | ft