Keep loosing Windows Update and MSN access

Greetings!

I run across a problem whereby I loose the ability to do Windows Update and
access MSN. My assumption is that something is happenning to the
configuration of IE or it's supporting DLL's.

I've done web searches and can usually fix the problem by reregistering a
handful of DLL's under the system32 directory. But the problem returns;
usually within a couple days.

I've run Spybot, HijackThis, A/V system scans but have found nothing to
attribute the problem to. Any recommendations are greatly appreciated.