According to GroupWise TID 10062639, "Auto-Archive not working", Auto-Archive by design only archives opened items.
This became a problem at our company since not all emails are opened by users, but the emails were important enough that they needed to be archived. Also users' mailboxes were becoming large and unmanageable. Marking emails as opened but unread would allow Auto Archiving to proceed with archiving previously unopened items. These unopened items were in the thousands. Imagine opening each mailbox and manually opening each item or highlighting thousands of emails and proceeding to archive.
This program allows you to set every message in every folder older than a certain date as opened. Once the user opens his email Auto-Archiving does the rest! There is a runtime status that lets you see which email and folder the program is currently working on. Maybe the next version will work on multiple users, have better error handling and reporting.
Use at own risk. Tested on GW 6.0.