Things to know to ensure a successful migration
The following is a list of critical information that you need to know in order for your migration to succeed.

• Before you upgrade, you should back up the database. Read the document: Best Practices for Disaster Recovery with Symantec Endpoint Protection.
• If your site uses replication, you must disable replication before upgrading Symantec Endpoint Protection Manager. You must disable replication at each site that replicates.

Review System Requirements and Known Issues
 

• Symantec Endpoint Protection 12.1 System Requirements
• Known Issues for Symantec Endpoint Protection 12.1
   

Upgrading the Symantec Endpoint Protection Manager to Enterprise Edition

1. Backup the database
2. Turn off replication
3. Upgrade the Symantec Endpoint Protection Manager (SEPM) software.
4. To start the upgrade browse to the root of the installation media for Symantec Endpoint Protection 12.1 Enterprise Edition and launch Setup.exe. Select Install Symantec Endpoint Protection Manager. A dialog box will appear and let you know that it is upgrading the licenses and software. When the Management Server Upgrade wizard appears click Next and wait for the upgrade to complete.
5. Login to the SEPM and apply your Enterprise Edition license file to complete the process. (Admin->Licenses->Activate License)

Upgrading the Symantec Endpoint Protection Clients to Enterprise Edition

• The clients will automatically update to Enterprise Edition on their next reboot.