Stand alone messaging gateway scanner password needs to be recovered.
Messaging Gateway
The scanner password is separate from the Control Center or other scanners. The password used to log into the scanner has been forgotten or does not appear to be working as expected.
Command line admin accounts cannot be retrieved from stand-alone scanners, there's no back door into a scanner.
If the admin account is lost, the scanner must be restored.
The Control Center has all the configurations for a scanner, it's designed to be quickly rebuilt if necessary. The Message Audit Log will not be retained in this case.
How to perform an OSRestore on Messaging Gateway
Symantec™ Messaging Gateway 10.8.0 Installation Guide
All configuration is stored on the Control Center appliance which has 'Forget password' recovery Reset admin password for Messaging Gateway
Please read How to Backup Message Audit Logs to move message audit logs from one scanner to another scanner.