Our mailboxes are set to retain deleted items in the "Recovered Deleted Items" folder for 8 days. We have found multiple mailboxes with email that is several months old.

Any help would be appreciated.

Thanks

See if below cmdlet helps...

Start-ManagedFolderAssistant -Identity "username"

Hi Mkent,

Also validate if the policy is correctly configured and applied to the users or not.

Get-RetentionPolicy | fl name,retentionpolicytaglinks

Get-Mailbox Username* | fl Name,RetentionPolicy

By Default:

Exchange Setup creates the retention policy Default MRM Policy. The Default MRM Policy is applied automatically to new mailboxes in Exchange Online. In Exchange Server, the policy is applied automatically if you create an archive for the new user  and dont specify a retention policy.

Hence it doesn't automatically apply to On-premise users not having archive mailboxes.

Apply a retention policy to mailboxes:

https://technet.microsoft.com/en-us/library/dd298052(v=exchg.150).as

Hi,

Please run the following command to check your deleted item retention for the problematic mailbox and database:

Get-Mailbox -Identity Mailbox1 | fl Identity, *DeletedItems*

Get-Database -Identity DB1 | fl Identity,*DeletedItems*

If you want to set it to 8 days, please run:

Set-Mailbox -Identity - "Mailbox1" -RetainDeletedItemsFor 8

Set-MailboxDatabase -Identity MDB2 -DeletedItemRetention 8

Regards,