Hello,
In your case, you need to login as "admin" user (without any domain).
Once, you are logged in, you may be able to make necessary changes.
NOTE: You are carrying a older version of SEP (11.0.3001), it is advised to migrate to the Latest version of SEP 11.0.7101 (SEP RU7 MP1).
Check this Article to find how Old version are you carrying:
What are the Symantec Endpoint Protection (SEP) versions released officially?
https://www-secure.symantec.com/connect/articles/what-are-symantec-endpoint-protection-sep-versions-released-officialy
It is important to maintain consitency in the SEP 11 - check article below:
About Maintaining Consistency of Software Versions throughout a SEP 11 Organization
http://www.symantec.com/docs/TECH131660
Migrating to Symantec Endpoint Protection 11.0.7101 (RU7 MP1)
http://www.symantec.com/docs/TECH171552
Hope that helps!!