BootCamp partion with many bad sectors on internal SSD

New MacBook Pro 16" 2019 with 2 TB SSD, 300 GB for Bootcamp, Winclone Standard version 8.2.

After restoring a Winclone image of my BootCamp partition, Windows 10 complained about low disk space because there was an unusually high number of sectors on the SSD marked as bad. Running chkdsk /r turned even more available space into bad sectors.

So, I decided to re-format the BootCamp partition in a Windows 10 recovery console. At first, “chkdsk /f” did not report any errors. But running “chkdsk /r” converted ALL sectors of the entire partion into bad sectors, reporting 0 KB available.

I suspect that this issue is caused by the Apple SSD driver. I’m using BooCamp version 6.1.7748 with the AppleSSD.sys driver version 6.1.7400.3 (03/19/2019).

Do you have a solution for this issue?

I have not heard of this issue before especially chkdsk marking all sectors as bad. Are you able to reformat it and does it show free space?


Yes, as I wrote before, I did format the BootCamp partition, and it looked fine, at first. “chkdsk /f” did not report any errors and the whole disk space was available. But after running “chkdsk /r”, ALL sectors of the partion were marked as bad sectors, and 0 KB was available. Since macOS is running just fine, I doubt that the SSD is defective. This only occurs in Windows, which is why I assume that there is something wrong with the AppleSSD.sys driver. Anyway, I could be wrong.

At least one person has experienced this issue before in this post:

I’m curious if anybody has experienced anything similar or even found a solution for this issue? If this is neither caused by Winclone, nor the AppleSSD.sys driver, then it is entirely possible that my MacBook has a hardware defect - either the SSD controller on the T2 chip or the SSD itself.

Have you checked the SMART data? Download the trial version of DriveDx and see what it has to say.

@ Mac_Doktor
DriveDx reports:
“Advanced S.M.A.R.T. Status: OK, 0 issues found”
“Overall Health Rating: GOOD, 100%”
“SSD Lifetime Left Indicator: GOOD, 100%”

Therefore, I doubt that this is a hardware issue. Since the restored Winclone image partition already contained a huge amount of bad sectors, one possibility is that Winclone has an issue with the new SSD controller, which is part of the new T2 chip. Or this is an issue with the WIndows driver supplied by Apple (AppleSSD.sys, version 6.1.7400.3, 03/19/2019).

Does anybody else experience this issue on their new MacBook Pro 16’’? Any ideas how to fix this?