Basically it says you need to delete your temporary internet files. Go to Tools - Internet Options - and under Temporary Internet Files click delete. If you want to delete all your temp files thoroughly download CCleaner
Can you open files in notepad? That is what Explorer uses to view web page source. If you can't then you need to reinstall notepad. If you can open files in notepad maybe someone else will have a better solution.
I don't think I'm dealing with quite the same pressures though, at the very least its a significantly smaller system. For the time being I'm just going to put together a quick scrubby box though and hope it works good enough to not make my house toxic
I do know this - xenforo dropped the ball by not keeping the vbulletin reputation comments as a feature. The loss of the Reputation comments data when we switched to Xenforo really was the death knell for the site when it came to all the users that left. I know I missed it so much and I got way less interested in the site when that feature was gone and I run the site.