Penny, I ran into similar problems a few months ago - it may actually have happened when IE8 installed, I'm not certain. One of the issues was that MS Word disappeared. Anyway, I searched on the MS site for a way to restore Word and found a script file there that apparently rebuilds the registry. It cured that problem OK.

Sometime later an unrelated problem came up. I accidently ran that script, not remembering what it was, and it repaired that problem too. I can't be more specific where to find the file without a search but it may save you some work if you can find it.

This is the text of the file with the caveat that I don't know anything about this stuff. More knowledgeable people here may be able to explain. To run it, copy into a txt file then change the txt extension to cmd:

cd /d "%ProgramFiles%\Windows Resource Kits\Tools"
subinacl /subkeyreg HKEY_LOCAL_MACHINE /grant=administrators=f /grant=system=f
subinacl /subkeyreg HKEY_CURRENT_USER /grant=administrators=f /grant=system=f
subinacl /subkeyreg HKEY_CLASSES_ROOT /grant=administrators=f /grant=system=f
subinacl /subdirectories %SystemDrive% /grant=administrators=f /grant=system=f
subinacl /subdirectories %windir%\*.* /grant=administrators=f /grant=system=f
secedit /configure /cfg %windir%\repair\secsetup.inf /db secsetup.sdb /verbose

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