NT 4.0 with Internet explorer 5.5

Hi guys

Can you give me any ideas on how to solve the following problem , Hopefully I do not need to reinstall NT

You can browse the internet fine no problems when you try to logon to
Hotmail you get an error message and will not let you logon. You can log on
from any other machine no problem.
If you log on the the computer as Local Admin it works fine but as yourself
it dont work !!
If you log in as yourself on anyother machine it works fine?

Operation System = NT 4
Browser = IE 5.5

I appreciate all your help in advance

Cheers

Martin