If you have a corrupt file in IE you can repair it (well try!) by going to Control Panel, highlighting IE6 and clicking on remove. This will not remove it but give you the opportunity to repair.
As far as the desktop icon is concerned, drag it to your waste bin, then go to the IE6 file, left click and accept the option for a short-cut onto your desktop. {This may clear the problem up before doing the IE6 repair}.
If all else fails, re-download IE6 from the Miscrosoft download site.