### Troubleshoot

#### Apple Mac OS and OSX

On Apple the application launch can be forbidden.

- For recent MacOS, if PropagationTool cannot be open, confirm opening in security panel: Open a Mac app from an unknown developer.
- For older MacOS, if PropagationTool launch shows the message App Is Damaged And Can’t Be Opened, use the command `sudo spctl --master-disable` in a terminal. Then, once application is launched a first time, use `sudo spctl --master-enable` to restore security.