You will notice that Mackup is no longer working if you sync your applications through Dropbox because the latest update has created another layer of security to take advantage of macOS Monterey privacy features.

The installed apps can’t read the preferences files because these files are located in a different Cloud Storage (for example, Dropbox)1 that requires additional permission if you want macOS to read these files.

You can resolve the permission issue by granting ``cfprefsd` with Full Disk Access.

It’s safe to grant permission to cfprefsd because it’s one of the tools used by the developers to read the macOS preferences files. You can read more about it here.

You can locate the file by entering which cfprefsd in Terminal. By default, you can find the file at this path:

/usr/sbin/cfprefsd

Open Security & Privacy in the System Preferences and drag the cfprefsd into the Privacy => Full Disk Access tab. You can log out and login into your user account to see if this resolves the problem.

Custom Mackup Directory Path

If you are still having problems with reading the preferences, you want to consider uninstalling Mackup and restoring the preferences files back to their original paths.

  1. Backup the latest preferences by entering mackup backup into Terminal. Enter Yes for all the preferences you want to backup.
  2. Enter mackup uninstall to restore the preferences file back to the default paths.
  3. Create a new file called .mackup.cfg in the Home directory and update with the following details. You can replace the value of directory with the directory name you use — the default directory name is Mackup.
[storage]
engine = file_system
path = Library/CloudStorage/Dropbox
directory = Mackup
  1. Enter mackup backup to create symlinks pointing to the paths you’ve configured above.

Restoring Backup

  1. To restore your preferences files on other macOS, you want to make sure that you have updated to the latest Dropbox and let the files complete syncing first.
  2. Create a .mackup.cfg and enter the same details you had before.
  3. Ensure that cfprefsd has the permission to Full Disk Access.
  4. Enter mackup restore to restore the files from Dropbox backup.
  1. For full discussion regarding this topic, you can learn from this discussion in the official repository.