I know it's been a while but I just dealt with an essentially identical error. Long story short, this was caused by a collision between two versions of Qt. There are several possible causes:
- The most common seems to be a plugin with its own version of Qt.
- In my case, it was an issue where PyInstaller wasn't getting my application pointed to the included version of Qt so it was conflicting with the general installation in my Library.
I actually removed my install of Qt to confirm that this was actually the issue (the app ran fine afterwards). By extension, you'd only see the issue among customers who have an installation of Qt.
Two ways users can diagnose the issue:
- Open the .app folder and navigate down to Contents/MacOS. Run the program from this location. You'll get a terminal showing errors like these: http://www.pyinstaller.org/ticket/472.
- Confirm the presence of a Qt install. (Temporarily) move the Qt Libraries and see if the app runs successfully.