Boxcryptor problems on macOS after migration to M1 (Silicon)

The change from an Intel-based Mac to a new Mac with M1 chip (Silicon) went almost perfectly for me. I chose the migration via TimeMashine and restored on the new hardware. Now Boxcryptor refused to work on the Silicon Mac. But there is a solution …

Problem

Boxcryptor complains about an unauthorized system extension. This is also described on the support page of Boxcryptor and first you have to convince the Mac to accept system extensions and updates from third parties via a reboot with the power button held down.

There you can solve the problem in the security settings:

“Enabling system extensions is an absolute requirement for using Boxcryptor on Apple Chip Macs and otherwise Boxcryptor will not work.”

“To use third-party kernel extensions on Apple Chip Macs, users must enable system extensions by changing their Mac’s security policy to Reduced Security and allowing user management of kernel extensions from identified developers. Despite the dramatic name, Reduced Security still provides the best security for any Mac”

Set everything accordingly and restarted the Mac. You will now be prompted to approve the system extension of “Benjamin Fleischer”. A reboot is then executed.

If the Mac is restarted again, a faulty system extension is reported and after confirming again, the approval of the extension of “Benjamin Fleischer” is requested again via the path described above due to a change of a system extension.

This goes on endlessly …

Solution

First of all, why is it crashing here?

Well, this obviously has to do with the Boxcryptor release, which now supports the M1 processor for the first time. Boxcryptor has packed both variants into one installation file and the kernel tries to load both extensions. This leads to the infinite loop and lets Boxcryptor fail.

In the meantime, Boxcryptor has released a new version that does not have this problem anymore. But: You have to uninstall the old version cleanly and especially reset all kernel extensions and their permissions.

And that’s what you have to do …

• First, completely remove the installed Boxcryptor version from the Mac (Finder -> Applications -> Throw Boxcryptor in the Trash).
• Shut down the Mac
• Start the Mac and keep the power button pressed until the system utilities are loaded.
• Login with the system password
  (if you have encrypted the boot volume, unlock it as well)
• Start a shell via Utilities -> Terminal
• Enter the following command:
  kmutil trigger-panic-medic --volume-root /Volumes/Macintosh\ HD
  If you have another boot volume, then replace “Macintosh / HD” accordingly
• Now restart the Mac. A message box with the “Panic Medic Boot” message should appear. This is a good sign 😉
• Now download and install the latest version of Boxcryptor from the manufacturer’s website
• One last time allow the system extension under System Preferences -> Security
• Restart the Mac
• Now it should work