First Aid on an Encrypted APFS TM Volume: 69845 Error

[Connie]

I ran Disk Utility First Aid to check an encrypted APFS Time Machine volume. First Aid ended with the error saying:

File system check exit code is 66.

Restoring the original state found as unmounted.

File system verify or repair failed. : (-69845)

What does the error mean?

[Wilsey]

I have the same encounter with you. The “File system verify or repair failed. : (-69845)” error indicates that the Time Machine volume is corrupted. It may be caused by sudden power failure, improper force ejection, virus attacks, etc.

To fix it, you should recover data on the volume and then reformat it.

To restore files on a corrupted drive or volume, you have to use a data recovery tool. iBoysoft Data Recovery for Mac is a professional data recovery software that supports restoring files from corrupted, inaccessible, unreadable, and unmountable hard drives and volumes.

I used this tool to get files off my corrupted drive last month. It is easy to use.

1. Download iBoysoft Data Recovery for Mac and install and open it on your Mac.
2. Ensure your TM volume is connected to your Mac.
3. Select the TM volume from the list on the software’s main interface and click Search for Lost Data.
   
   
4. After scanning, check the results, select the wanted files, preview them, and click Recover to save them to a different destination.
   
   

[amandawmm]

This issue is a bug in macOS. My Time Machine drive can back up my M1 MacBook (Big Sur 11.1) normally, but Disk Utility First Aid gives me the error “File system verify or repair failed. : (-69845)” as well.

Before updating to Big Sur 11.1, there was no such problem.

So, I suppose that the system bug may be the cause of this trouble.

Before reformatting your drive or volume to fix it, you can try updating your Mac.