MacBook Pro (2016) with 256GB SSD, 150GB for Bootcamp. Ran chkdsk /b as recommended before saving Winclone 6 image. About 90% of Bootcamp partition is now flagged with bad sectors. Rerunning chkdsk /b is no help. Neither are MacOS disk tools.
Sounds like you are having disk errors and I would proceed cautiously. You may need to replace the drive.
I have this problem as well. It’s a brand new computer and Apple’s Disk Utility says the disk is fine.
Does chkdsk give the errors or Winclone?
Chkdsk /b runs until it hangs and the machine reboots automatically. When I check the Windows partition after that, there is almost no remaining free space.
After this happened the first time, I wiped the partition in Disk Utility and restored from a Winclone backup. Then I ran chkdsk with the same space-gobbling result.
After wiping the partition again and restoring, Windows is now running fine. Somehow, however, the amount of space used on the partition is unreasonably large, about twice the size of the Winclone backup.