My suggestion is going to be Reinstall or Upgrade to Internet Explorer 6. This will fix any changed/altered files that appear.
Here is a direct link to the Internet Explorer 6 English Download.
http://download.microsoft.com/download/ie6sp1/fin...EN-US/ie6setup.exe
Now in your Control Panel > Add Remove Programs you should see something liek Microsoft Internet Explorer 6 SP1 or Internet Explorer 6 SP1 you want to click on that and hit Remove.
You will get a screen asking you to Reinstall Choose that.
You can also type this into the Run Command (Start > run)
rundll32 setupwbv.dll,IE6Maintenance "C:\Program Files\Internet Explorer\Setup\SETUP.EXE" /g "C:\WINDOWS\IE Uninstall Log.Txt"
This will bring up the same window.
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