unzipping (a .zip file) produces (a .cpzip file)

Daniel Drijard <[email protected]> Fri, 6 Apr 2018 17:54:22 +0000

Newsgroups	gmane.comp.lang.realbasic.user
Message-ID	<[email protected]>

Hello,

   A friend of mine has a problem he does not understand. He requested help from me, but I am helpless. I hope somebody could help.
   We are both using Macs from APPLE system.
   I sent him by email a folder containing a few files. My email system (MAIL) decided to group these files into a .zip file. After reception, my friend 2-clicked this file and got a new file with the extension .cpzip. 2-clicking this file produces a file with the extension .zip. This is evidently endless !
   Searching internet, I did not find which software may like this extension.
   Please help us.

Cordially,
Daniel

Daniel Drijard
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