can generally be traced back to bad, corrupted, or malware infected add-ons.

You have a few options.

1] Scan with your anti-malware scanner. I use Malwarebytes' Anti-malware

2] Do an elimination test with your add-ons. They are listed in IE > Tools > Manage Add-ons. The test is to see if any are causing your problems by disabling, then testing.

3] The brute force option. In IE8 > Tools > Internet Options > Advanced tab there is a Reset button. Clicking that button will revert IE8 back to default, no add-ons, but also no favorites, no history, no cookies, and no 'saved' logins and passwords. You can export the favorites beforehand and import them back afterwards, but not the others.

Mark