NT 4.0 AND Office XP

I am currently having a problem using Office XP (specifically Outlook) on a windows nt 4.0 machine. I keep getting an error that states "Outlook requires Outlook express 4.01 or greater. Install Outlook express 5.0 by running IEsetup.exe..). I installed that from the XP cd and it still doesn't work. I looked up microsoft's knowledge base article-Q212991 and followed those instructions. Still coming up with the same error. Any ideas, please?