My first though is that your problem might be path-related. I'd suggest providing the full path to the unzip command. It's quite possible that the web server doesn't have unzip in its path.
I have a very similar script that I run on a machine at home. I'll check it this evening and add to this comment if I find anything else that might be helpful for you.

In reply to Re: Script to unzip a zip file on the server...... by ScooterQ
in thread Script to unzip a zip file on the server...... by Anonymous Monk

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