It really depends on what antivirus you're using. For example, I'm running an older version of N.A. Corporate Ed. I open it up, go to configure, click the Real-Time File Protection subtree, and look for a button that says Exclude Files and Folders. You're probably using something else, but it shouldn't be to hard to figure out. Just dick around with the program for a little bit and you'll get it.
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Pugna Bellum - Fight the Battle. I will fight the battle.