In the drop-down box select "Email scanning only" or "Both Control Center Authorization and Email Scanning"
Ensure that "Enable end user quarantine" is enabled in two places
(Spam -> Quarantine Settings -> End User Settings) Under "End User Settings", check "Enable Quarantine".
(Administration -> Policy Groups -> Select the Policy Group to allow End User Quarantine -> End Users tab) Check " (Repeat for any additional Policy Groups that will be allowed to login to their end user Quarantine)
Verify if an end user account can successfully login to the control center and view their quarantine.
Spam Quarantine notifications are enabled by default to be sent once a day (everyday at 4:00), with the following criteria:
Only users in policy groups that have end user quarantine enabled will recieve notifications.
Spam quarantine notifications will only be sent to users that have new spam messages since the last time the quarantine notification was sent out.
If spam quarantine notifications are not delivered, go to (Administration -> Control Center -> SMTP) and select "Define new host" and enter the mail server's IP and port. (NOTE: This is a workaround for having internal DNS MX records for your mail server and will only allow you to release messages from quarantine that are destined for the individual mail server configured)