MG Connection Failure

I'm running Vista Ultra and for the past 2 weeks have been unable to connect to MG's (am on other com now lol) I have exhausted looking through all Tools settings in IE and am just about to pull me hair out whats left of it.. Synopsis No FW/No Defender activated/popups allowed and have physically typed MG address where-ever possible. I see no physical signs on screen when trying to connect it just cannot find URL and comes up with check your Network settings.. I have NO problem connecting elsewhere although on one site I can reach when I press the purchase button I get the same response as trying to connect here... Any ideas fellow Geeks ???