Chkdsk is running on media that does not support writes in place. On such media chkdsk operation is limited to verifying ...

Chkdsk is running on media that does not support writes in place.
On such media chkdsk operation is limited to verifying the presence
of a valid VAT on the last written block and if necessary searching
for the last valid VAT and placing it at the end of the disk.
This could revert the media to a previous state before the corruption
occured.