Well go to your Add/Remove programs properties box .Then next select Internet Explorer.
Then you should see three options if I am correct ...
1]Add a component
2]Repair Internet Explorer
3]Restore The previous Windows Configuration
Select the second option ... What it will do is try and fix anything that might be wrong with your Internet Explorer.
Hope that helps ...
Do you know what the error is... If you could write it down it would kinda help ...
Agent_Steal this doesn't work with all windows OSs but I guess it's a good start for the little info given.

Internet explorer can be a pain at times. But this could also be caused by an update gone bad. If it's an update that caused this just get the update from some other source and install it that may solve the problem.

With a little more info we might be able to give you a more direct answer.

Guidance...