I am getting this error every day now and had a good backup probably 10 days ago.
This has happened again today after the backup was about 78% completed. When this error pops up, I cannot even access my USB plugged in external drive. The only thing I can do is to format HDD and try all over again.
I have ran chkdsk/f on the drive and checkdisk did not find any problems with the external HDD.
What do you think can cause this?