My guess is that when he is clicking on Internet Explorer it works the first time but then it becomes a file not found from the start menu. This is typical from some malware after it has been removed.
Go into your Control Panel and click on Internet Options. Click on Advanced. Click on Restore Defaults. Click Apply. Go back to the General tab and click on Delete. Click Apply. Click OK until you're back to your desktop.
Now, right click on the start menu icon and click on Properties. Click the Start Menu tab and click Customize. Inside of this menu, next to Internet (make sure internet is checked), choose Internet Explorer. (Please tell me if there are two internet explorer's listed here, that means one if false (malware) and one is the real IE). Click Apply and OK until you're back to the desktop.
Now, test the IT icon on your start menu. If it still doesn't work and there WAS two options from above, go back in and select the other one and test.