You've purchased a license for Messaging Gateway but have lost or do not have the license file needed to register / renew a Messaging Gateway system.
Information on obtaining and renewing your product licenses can be found in the following article:
Each Scanner that you install and enable to use Symantec Messaging Gateway features must be individually registered using your license file. You can use the same license file to register multiple Scanners.
Note: The basic product functionality for Symantec Messaging Gateway requires a single license. In addition to this license, you can also obtain a separate license to enable Symantec Content Encryption. Content encryption lets you encrypt outbound messages for greater security and to track statistics for those messages through the Control Center.
When you obtain your license file from Broadcom, save it to a location that you can access from the Control Center.
To license your product
In the Control Center, click Administration > Hosts > Licenses.
Click Browse and locate the license file.
Click Register License.