Your description of the problem is very good but you have not included any technical information. Your OS? The firewalls you have? Modem info? Wired to the modem or wifi? Desktop or laptop? How many computers in the home? Are all the computers wired or are they wifi? Is the game loaded on more than one computer in the home? Etc. . . . .?
(My guess at this point) Based on the description that you have provided it seems that your firewall may be blocking the game. The symptoms you describe are exactly what players see after a game patch and a firewall blocks the new game .exe or the game .dll.
I know, you shut off your firewall. One thing you may not be aware of is that Norton, Zonealarm and perhaps other firewalls default to block all ports (except 80 for the browser) when the firewall is disabled. Norton and Zonealarm (and perhaps some others) need to be configured and active or uninstalled but not prevented from running. Preventing Norton or Zonealarm from running just creates or adds to the problems.
Did Windows update run/change anything between the first time you logged in to when you were having trouble? Did the game update between the first time you logged in and when you started having trouble?
Edit: I would suggest that you google info about your firewall and find out how to add the game .exe and the game .dll to the permission list.
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The art of war is simple enough. Find out where your enemy is.
Get at him as soon as you can. Strike him as hard as you can,
and keep moving. - Ulysses S. Grant
Only the dead have seen the end of war - Plato
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