before you try a format do the following
If you are running any Anti Virus - disable it (testing only, dont do permantly)
If you have a content filter installed such as netnanny or content watch - disable it
disable Windows defender
Ensure that your antivirus doesnt include a firewall with it.
In IE 8 go to tools -> internet options -> advanced -> reset, reset all options. Please note this will remove any saved credentials and passwords. After the reset close down IE and all processes associated with it.
IF this resolves your problem it would be helpful if you went through and re-enabled everything 1 at a time and see if it breaks the game again. If it does break it, disable it, test again. If you find the problem it would program it would be great if you posted your results