IE5 Wizard Error

When trying to install Outlook 2000 I’ve run into an error on a couple of PC’s that give me an Internet Explorer 5.0 Wizard error and halt the installation process. I’ve tried to reinstall the IE5.0 and encounter the exact same error. I’ve returnedthe PC to IE 4 and encounter an IE 4.0 Wizard error. No matter what I seem to try I cannot overcome this error. Any suggestions???