A friend of mine applied a system update (Catalina) on his Mac, and after that the system got corrupted somehow. When I connect the Mac to my Mac (with Target Mode) I can see Macintosh HD and Macintosh HD - Data. On Macintosh HD there are no files, but I can see files on the Data volume, however when trying to copy files from that volume I get errors…
It was a couple of years ago I had these kind of problems on any Mac. Earlier I have used Diskwarrior for many years, but that doesn’t suport APFS. So what do one use nowadays for data recovery?
Google gives a lot of answers, and many of them seems to be paid…
I just accidentally deleted files off an SD card, and so went searching.
Disk Drill seems really well regarded and I downloaded it, but couldn’t recover my RAW photos in the free version. So, I went to the App Store and found Data Recovery Essential.
It allows 100 MB free per day, which I love as a model since I get to try it out, perhaps build loyalty, then shell out when I really need it.
It worked perfectly, claims it supports APFS, and it turns out it’s by the same company as Disk Drill. I’m confused by this!
It turned out that the Samsung EVO 850 SSD was defect.
I managed to mount the Macintosh HD - Data partition (after a lot of struggle) and copy all files but one that was damaged.
After that I swapped the defect drive for a new one, installed a new system and used my copy as source for the Migration Assistent.