Symptoms
After updating to macOS 10.15.4 backups fail with the following error:
The last backup has failed. Failed to enumerate directory 'Macintosh HD — Data:/private/var/db/lockdown/'. It may be corrupted or does not exist. Please check the disk for errors.
Cause
Catalina update 10.15.4 restricted access to folder /private/var/db/lockdown/ for security reasons.
Solution
This issue has been fixed in Acronis True Image 2020 Update 3 (Build 25760), please update to the latest build. Starting from this version, folder /private/var/db/lockdown/ will be automatically skipped.
If you cannot install the latest build for some reason, as a workaround, exclude folder /private/var/db/lockdown/ from backup:
- When configuring a backup, click Settings, and then click Exclusions;
- Click the Plus sign to add a new exclusion;
- Most likely the folder will not be present in the list as it is hidden by default. Press the Command + Shift + . (Period) keys at the same time to show the hidden files and folders on Mac. Browse to the folder /var/db/lockdown/, select it and click Exclude.
Press the Command + Shift + . (Period) again to hide hidden folders.