Problem with Internet Explorer 6.0 SP1 and opening links

I have a Windows 98SE PC running Norton Internet Security 2005 Spyware
Edition. I am unable to open links from Outlook Express into Internet
Explorer. What happens is that a new IE window opens but just sits there- no
internet traffic from that windows, not even the homepage. I am also unable
to do a right click, open a new Window on a link on a web in IE. Plus I am
also unable to find a word on a web page in IE (error message - 'A error has
occured in this dialog. Error: 25 - Incompatible version of the RPC Stub').
Also I am unable to download updates via Windows Update in IE. I have tried
disabling NIS 2005, re-install IE 6 SP1 - unsuccessful. Have installed
Firefox 1.0.7 - opening links into Firebox (now as default browser) from
Outlook Express work perfectly so I don't think the problem is in Outlook
Express.