Can't run app because of permission in Big Sur

The problem in my case it was related to a Big Sur problem where UPX compressed binaries are not recognised properly so not executed with a permission error. There is some more info here: https://github.com/upx/upx/issues/424

So the solution is to unpack the binary with UPX and run it normally.

Install upx with brew:

brew install upx

now run this command:

sudo upx -d /Applications/my_app.app/Contents/MacOS/my_app

(please note you have to specify the full binary path)

you should put the path of your binary instead of "/Applications/my_app.app/Contents/MacOS/my_app"

Then run the application normally.

I had this problem with the error "Termination Reason: Namespace CODESIGNING, Code 0x1" and

I managed to open application after I signed it again on that machine, with the command:

codesign --force --deep --sign - /Applications/AppName.app

No other solution worked for me.

Open Terminal or iTerm and type sudo chmod -R 755, then drag the .app into the window, which will bring the full path into Terminal or iTerm. This worked for me, moving the -R option directly after chmod.

It will look like this:

sudo chmod -R 755 Path\ to\ app\ file.app

Press return.