Driving me crazy!

Okay, every now and then when I try to install something it comes up with this error '1608: Unable to create InstallDriver instance, Return Code: -2147024894'.
Now I've been directed to this page 'http://consumer.installshield.com/kb.asp?id=Q108440' and i've tried everything.

Now my problem is that when I try to configure the DCOM settings it keeps closing. I run dcomcnfg and that works fine, I click Component services and that works fine also. But then when I click the folder Computers it just closes and it closes every time I do it. Why does it close? This is really driving me crazy because I can't install the software needed for my iPod that I just bought for $350 and atleast half of the games I want to play don't work either.

I am running Windows Xp Professional with the Service pack 2 installed.
Please someone help me.