How to fix/repair invalid APFS object map error?

"I couldn't mount one of my APFS volumes on macOS High Sierra this morning, so I ran Disk Utility to check and repair it. But I got an error message: "APFS object map is invalid". I searched it on the internet but didn't find a useful answer to fix the "APFS object map is invalid" error. Anyone can help me?"

Disk Utility is a Mac build-in tool to manage internal disks and external storage devices. Disk Utility's First Aid is able to detect and repair damaged disks. But it is only helpful to fix a minor problem. Such a serious error like APFS invalid object map that First Aid can't repair.

The "APFS object map is invalid" error on macOS 12 Monterey, macOS 11 Big Sur, Catalina 10.15/Mojave 10.14/High Sierra 10.13 refers to the damaged APFS object map. As the APFS object map consists of important file system information, if it is damaged, the macOS fails to recognize the APFS file system. Consequently, the APFS drive cannot be mounted and we are not allowed to access the APFS drive nor the files stored on it.

Two simple steps to fix/repair "APFS object map is invalid" on High Sierra

Since First Aid cannot repair the "APFS object map is invalid" error on macOS, to avoid data loss, we have to recover lost data from the APFS volume as soon as possible, and then reformat the APFS drive. Here we recommend you Mac data recovery software – iBoysoft Mac Data Recovery.

Step 1: Recover lost data from APFS volume when its APFS object map is invalid on macOS High Sierra

iBoysoft Data Recovery for Mac is the best APFS data recovery software that can recover lost data from APFS volume when its APFS object map is invalid, recover lost data from formatted APFS hard drive, recover lost data from unmountable APFS drive, recover lost data from unreadable APFS hard drive, recover lost data from corrupted APFS drive, recover lost data from encrypted APFS volume, recover deleted/lost APFS partition, etc.

Besides, iBoysoft Data Recovery for Mac can also recover lost data from unreadable hard drives, recover lost data from unrecognized hard drives, recover lost data from corrupted hard drives, recover lost data from unmountable hard drives, recover lost data from inaccessible hard drives, recover lost data from uninitialized hard drive, etc. on macOS 10.14/10.13/10.12/10.11/10.10/10.9/10.8/10.7.

Tutorial to recover lost data from APFS volume when its APFS object map is invalid with iBoysoft Data Recovery for Mac

Step 2: Fix the "APFS object map is invalid" error on High Sierra by reformatting

After recovering data from the corrupted APFS volume, we can erase this APFS volume to make it work on Mac again.