I have a normal zip-file (close to 1 GB). I hided it with HIDE FOLDER; sometimes I unhided it ("Show"), than "HIDE" again. It worked normally before the hiding and unhiding. Now, when shown I click on it or double click and it says "Cannot unpack; format is not supported." The name is just "archive Oh.zip". All this on a MacBook Air early 2014, Catalina 10.15.1
I have no backup of this file.
If a normal reboot doesn't help boot into Safe Mode (How to use safe mode on your Mac - Apple Support) by booting with the Shift key held down and check there to see if the problem persists. Reboot normally and test again.
NOTE: Safe Mode boot can take up to 10 minutes as it's doing some system cache cleaning, volume verifying and directory repairing.
Can you tell us in detail how you went about this hiding and unhiding? What is "hide folder"? There is no such command in the Finder. Is this some Automator workflow or Applescript?
Hide Folders is an application from the AppStore.
I fail to see how a properly designed application would cause this.
Showing or hiding a file would only affect the metadata and not the data of the file.
Did you try restarting your mac?
Cannot unpack zip-file.
