If you were my neighbour I'd tell to to put the file on a USB stick and bring it over and I'd fix it, but that's likely not practical.

You could have done it in less time than it took to type the above message.  Unless you are logged in as a superuser you can't hurt much even if you tried to.

1. Drag a copy of the file to your Home folder.

2. Navigate to your Applications folder, open Utilities, and double click on Terminal.

3. Type or paste this at the Terminal prompt, substututing 'Filername'zip' with your file name(you can name the output file [FixedFilename.zip] anything you want so long as it is a unique name):

      zip -F Filename.zip --out FixedFilename.zip

EDIT; I looked in the manual and it recommends trying it with a single 'F' option first.  If it doesn't work, try -FF after the 'zip'  place of -F)

4.  It will either work, or it won't.  If it works you will get a list of files recovered.  When it finishes and goes back to the prompt, close Terminal. 

You are now a UNIX Guru for a day, and you've got your file back...

 

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The Wisdom of bagginsbill:

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