I am unable to access the internet to a number of sites such as gmail. The error message that keep coming up is "THE REQUEST LOOKUP KEY WAS NOT FOUND IN ANY ACTIVAITON CONTEXT"

I am using IE8.

Thank you

Assuming you upgraded to ie8

If you uninstall ie8 and let it go back to prevoius version, it should resolve the issue - at this point you can try to install Ie8 again to see if issue would return