selling LapTop is one pass enough

ok no replies to my last post re failing wipe clean so fingers crossed on this one- when i run ccleaner it wont finish the 35 pass wipe clean of free space - it keeps failing after an hour or so and not even quarter complete. Im selling my laptop to a stranger (friend of friend) and have deleted all my documents on laptop but due to my employment many of these were career review documnets including disciplinary issues for staff. Some very confidential.

Is one pass enough to prevent the documents being recovered?

Ta

Please stick with your original thread, and apparently this thread is the fourth you've opened about the same problem. Members notice this multi-posting, and tend to ignore them all as it results in replies being fragmented between the various duplicate posts.

http://forum.piriform.com/index.php?showtopic=32870

If someone has an answer for you they'll post it.