"The currently selected folder for backups and exports is not accessible."

[mtotschnig]

After restoring a backup, we keep the folder configuration from the backup, which might not work, because, user did not select it via SAF UI, and hence permission is not granted.
We should prevent this situation from happening, by checking after restore, if the folder configured in the backup works, if not keep the one configured before backup was restored, or fall back to default folder.