When you apply a Messaging Records Management (MRM) policy to the mailbox, the items in the Sync Issues folder may have an expiration date that is stamped on the items. However, MRM does not process or delete the items.
The reason that the items are listed as expired is that Outlook in Cached Exchange mode pulls the policy tag information for the folder and then does the calculation for expiration itself.
Additionally, if you want to automatically empty the Sync Issues folder, you must use the Auto Archive functionality in Outlook.
Synchronization errors foldersFor more information about the synchronization issues folders, go to the following Microsoft Office website:
The information in this folder may help your organization's support team or Microsoft Exchange server administrator determine what is wrong. The contents of the Sync Issues folder are not copied to your server, and you cannot view the items in the Sync Issues folder from any other computer.
Mail Item Expiration Date propertyFor more information about the Mail Item Expiration Date property, go to the following Microsoft Developer Network (MSDN) website:
For more information about Retention Policies and Retention Tags, go to the following Microsoft Exchange Server website: