Stubborn Symantec Antivirus 8

Priviously the dude before me installed Symantec Antivirus 8 on the client pc. Know i want to upgrade to Symantec Antivirus 9, and i can’t uninstall coz of this password from the Client’s Symantec Server to uninstall the program.
How cani get past this Password??? Do i manually delete the programm files or is there other ways around this…..
Ta Phil