There are allot of people having trouble with McAfee right now and it is known to block limewire. Try turning it off and seee if LimeWire will connect.
To disable firewall protection:
On the McAfee SecurityCenter pane, do one of the following:
Click Internet & Network, and then Configure.
Click Advanced Menu, then Configure on the Home pane, and then point to Internet & Network.
On the Internet & Network Configuration pane, under Firewall protection is enabled, select Off.
A warning appears saying 'When firewall protection is disabled, your computer is vulnerable to intrusion and unwanted network connections'.
In the warning box, you have the option of automatically re-enabling the firewall after 15 minutes (you can change this to 30 minutes, 45 minutes or 60 minutes).
Click OK to disable the firewall. Clicking Cancel leaves the Firewall protection enabled.
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