Which version of Internet explorer are you using? If you are using 7 or above, reset the internet explorer settings etc.
Open Internet Explorer, click Tools > click Internet Options > Click Advanced Tab > Click RESET. Select "Delete Personal Settings". Click ok. This will reset your internet explorer to the state when you first installed your windows OS.
If you are using Internet Explorer 6.0, upgrade it to minimum version 8.0. A free copy can be obtained from either windows updates or the Microsoft website.