Folder Auto-Clean is a method of limiting how much of your account disk space is used by the Junk E-Mail, Sent Items, and Deleted Items folders. As the domain email administrator, you can setup folder auto-clean rules for all email accounts under the same domain name.

To do so:

1. Under "Domain Settings" click on "Domain Folder Auto-Clean"
2. Then, under the "Options" tab, check the "Override auto-clean settings for this domain"
3. This will activated the the "Add Rule" icon (next to "Save")
4. Click on the "Add Rule" icon. This will open the "Auto-Clean Rule" page where you can set the parameters for domain folder auto-clean
5. When you are ready, click on "Save"