The world is full of fiddlers. You know people who do something they are not supposed to and then not know how to fix it. I see this a lot with Companyweb on SBS 2011 for the simple reason that most network users are given too many rights.
One of the issues that is apparently occurring more and more is that people are mucking up teh default homepage on Companyweb 2011. Getting it back can be a pain but Microsoft have released with KB article that should help.
http://support.microsoft.com/?kbid=2539296
Basically you need to run a provide powershell script and you should be back to normal.
I haven’t as yet tested this myself but will soon hopefully.
CIAOPS 