PC-Doctor's Surface Scan Test reads entire tracks beginning with the center track and moving outward to the maximum track. If any errors occur when reading a track, the Hard Drive test logs an error. This test scans for surface defects on the hard disk media. A quick summary from HP for surface scan test error code:
HD535-2W: Surface scan Error on disk surface
A chkdsk /f should mark this area as bad and avoid it in the future. You should however keep a close eye on this disk. In my experience when drives start getting bad sectors it can escalate rapidly. If there is a surface defect, scraped off oxide on the platter, the particles can float around inside the drive wreaking havoc and eventually causing complete failure.
-Fred
