Well, here I am with another necro post, because I read something so stupid I just had to respond, because I KNOW that this idiots post will remain here for years to come and people will have this problem continuously:
Paperdoc :
As sub mesa said, go to the WD website and download their diagnostic suite, Data Lifegard. Especially for your situation I prefer the version that has you burn your own diagnostic disk to a CD-R. You boot from that optical drive to run the tests independently of any OS or hard drive.
Using that, run the Zero-Fill option. It will force the HDD's own built-in testing process to check every sector and substitute hidden good spares for the real faulty ones. If there really are that many bad sectors, it will run out of spares and the task will fail. If you get to that point, THROW IT OUT! ... crap.... THROW IT OUT!
OK, just shut up and stop giving out advice. In an ideal world where everyone has a guaranteed minimum income and people don't worry about money, then yes they can just throw shit away and not worry. Now back to reality....where you don't know what you are even talking about, and some people are students, broke, poor, hate waste, whatever...
The WD web site sucks and consumers will end up with a number of different links to data diagnostics and other crap and have no idea when and if they should install. There are number of reasons people will get told that they bad sectors in "SMART" when they have no problem at all. For example. Using an old version of WD Diagnostics with a newer drive or vice versa will show you lots of red WARNING! messages telling you that "DRIVE FAILURE IMMINENT!!!" when all that has happened is that LAZY STUPID Western Digital developers did no put in any effort in identifying whether the drive even works with their software. This would have taken approximately 5 minutes and functioning brain. Consumers assume the NEWEST version will identify old drives which for some dumb ass reason (too long to explain here, but rest assured it has to do with corporate laziness and stupidity) the software won't support anymore.
Paperdoc :
If that all happens, it suggests that the original Windows tools that said you had 20% bad sectors was grossly wrong.
No, again you don't even know what you're talking about.
Paperdoc :
You cannot move bad sectors around on a disk.
THIS IS THE ONLY PART OF THE RESPONSE WHICH IS TRUE.
However there are some workarounds....
Paperdoc :
It is nearly impossible to arrange to have all the bad sectors in one Partition you never use. A Partition is simply an area of physical space on the drive platter surface that MUST be one contiguous block, and it is used as one logical "drive". So hypothetically it might be possible to have a whole chunk of disk space in one block damaged by some event. And in that case, with a LOT of fancy diagnostics you might be able to determine exactly where that block is and create a Partition there that you don't Format or use.
Hypothetically? Nearly Impossible? Fancy Diagnostics?
Please shut up and stop posting to technical support web sites when you have no f-ing clue as to what you are saying.
THIS HAPPENS ALL THE TIME!! A series of bad blocks occurs in one area of the drive, for whatever reason, very common, AND the best possible outcome, because now you have some options.
HDDTune the free version, EASUS, etc will visually show you a map of where these bad blocks are occuring, and if it is in one general area of the drive. Then you use simple math to arrange a partition which excludes the damaged portion of the drive.
Paperdoc :
It is very unlikely, but possible.
Of course, what that also means is that you then would have to create separate other Partitions before and after that useless block of space, and use those other two good Partitions as separate drives.
Tools like EASUS and Minitool make this process easy. You are also assuming the damage is occurring in the middle of the drive.
Paperdoc :
But then you'd still start to worry: why did one block get damaged? Will it happen again? Did the catastrophe damage some other internal part that is waiting to fail, too?
Nothing in life is a sure thing. People worry about lots of things, are you a therapist now too? Perhaps it will happen again, or perhaps, like has occurred with me, it was a one time event, the new partition avoids the damaged area of the disk, and the computer has worked fine for three years....
------------------------ july 2016 update ----------
my drive still working flawlessly, because I don't listen to dumb crap I read on the internet.
why this isn't marked best answer, I have no idea, i guess I'm just not 'nice' enough when presenting competent responses to problems. it doesn't matter either way, I will got out of my way to avoid this site and others until another problem crops up a year from now. this is still best place to get real answers to questions, unlike "black box" moron forums where "helpers" make all sorts of demands and then create custom scripts to 'help' users fix their issues. At least here, you an expect that sometimes there will be a real answer with actual details.
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