I use Norton and it will quarantine files if it is not trusted. You can turn auto-protect off and download and extract and then right click on file and click on file insight. It might say user not trusted and you can click on trust now. I get around doing this all the time by putting it in a file folder that is exempt from auto-protect.Some Anti virus software delete files from within compressed archives, don't know why it does it with the game though, if someone has AV problems please tell me what's the reason the AV gives for putting the files in quarantine.
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