If Method 2 fails try running management server configuration wizard once then try the same process again.
If your still not able to reset the password and if you do not many client reporting to the server you might want to try .
Symantec Endpoint Protection 12.1: Best Practices for Disaster Recovery with the Symantec Endpoint Protection Manager:
http://www.symantec.com/docs/TECH160736
and then
Restoring client-server communications with Communication Update Package Deployment