Upgraded to IE5.5, win update error

I just upgraded two of my computers to IE5.5 (so I’ll be able to access a certain company related website that runs script coding that needs 5.5 to run) — Now when I try to go into Windows Update – it won’t open the page, I can access any other webpage I want except for the windows update page — when I pull up the properties for the page, it indicates the address as being res://C:\windows\system\shdoc**** … and this is an error file ??? please help!?