WIN NT logon edits my registry

I have been issues a laptop for work and the OS is WIN NT 4 for workgroups. I have edited the registry to stop dispaly the company policy garbage at the begining each time I log on to the PC. But everytime I log on to the network, my registry is changed back to displaying this stuff. Is there way i can stop the log on from editing my registry? When I dont log on to the network (work off line), my registry is fine the way i have edited it.