Problems with IE 5.5 SP1 & Q290108

I have mainly NT4 Workstation PC’s. After applying SP1 to IE 5.5 and the Hotfix Q290108 (Incorrect Mime Header …) I have 3 out of 200 PC’s that will only let administrators use the Internet. Everybody else who logs on as a regular user gets an error stating, the address is typed incorrect.

Suggestions?