File Share Encryption

I have a PC that I have decrypted the drive from the management server but I am now unable to remove the program from add remove programs because the Client administrator password is not working. How can I reset this password for this client and uninstall the program?

As you've successfully decrypted the drive from the Management Server, this is clearly in a managed state.  Just apply a policy to change the client admin creds.

The below article is an old one but shows how to change the client admin creds.  NOTE, if amending via GPO just be aware the client administrators section is under Drive Encryption in SEE11 (there's no ambiguity in the Native Policies, as the client admins section is unavoidable and you'll eventually get to it):

http://www.symantec.com/docs/TECH161649