Hi W3bbo - thanks for the response & suggestions. Starting 'Internet Explorer (No Add-ons)' is no different and has no positive effect. IE still doesn't launch, and other programs still won't start etc, as per the original problem. As I said, can't kill the IE process using Task Manager. Tried your suggested command line but unfortunately, still no joy - go to 'Run' > type 'cmd.exe' > hit 'Ok' but nothing happens. The command prompt simply doesn't appear - so it is not even possible to enter your suggested command line. IE still doesn't launch and, again, I have to hard reboot the machine. For the record, all programs / applications / cmd.exe etc seem to launch and work just fine as long as I have not tried to start IE first. Trying to launch IE (with or without Add-ons) is the cause of the subsequent problems. For your reference, my version of IE is 8.0.6001.18702IS (I have retrieved this via 3rd party software, as I am obviously not able to successfully launch IE to check the version number!). I use Firefox, not IE, as my browser. I only use IE when I had to (e.g. Microsoft Update, certain online AV scanners etc). I really like the changes that XPize has made to my system and, ideally, I would like to keep it installed and benefit from the improved appearance. So in order to try and get around this problem I have just installed the 'Coral IE Tab' Firefox extension (https://addons.mozilla.org/en-US/firefox/addon/10909) - which enables me to use the embedded IE engine within tabs of Firefox. This extension appears to work fine and I am able to access Microsoft Update from within FF. - Why would the IE engine work ok within FF like this, yet not as a standalone application? Despite the fact that I can hopefully alleviate the need to ever use IE, by using this FF extension, I would obviously still like to try and resolve the problem and get things working 100%. - How do I correctly uninstall XPize? (Add & Remove Programs?) - When you suggest uninstalling XPize and you say, 'which will restore your system files to thier original state, it doesn't "unpatch" them' - does that mean that my system WILL or WILL NOT go back to exactly how it looked before I installed XPize (the standard Microsoft Zune theme)? What XPize changes, if any, would remain? Thanks very much. Rob