Edit: I got a couple of steps for you to try, fallow the pics
1)Open Norton
2) Click Settings in the Network Tab
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3) Scroll to the Smart Firewall Settings and click Program Control
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4) Find Warcraft III Change Drop down to Allow, Then click Modify in both screens that pop up.
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5) Make sure all the settings match these ones. Leave the last 2 tabs alone, Exit everything restart Warcraft 3 and see if that works
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