Run CHKDSK before SpinRite?

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Feb 13, 2023
TLDR: Should I run CHKDSK on the disk before running SpinRite?

New SpinRite 6.0 purchaser, hoping to rescue some data from a 1TB seagate HDD. Windows had been complaining that the disk was corrupt and offered to fix it. We tried this a few times but the folders/files on the disk were inaccessible and at times the volume did not even show up (IE E: drive not present in Windows Explorer)
Another symptom is, if the drive mounted properly, you'd try to navigate to a folder and get a popup saying "E:\Users\foobar\Downloads is not accessible. A device which does not exist was specified"

Anyhoo ... I'm wanting to run SpinRite on this disk and see if it can improve it or recover some of the files.

I see a section in the manual regarding CHKDSK ... should I run CHKDSK on this disk before running SpinRite?

Thanks for any advice!
You may be confused about what SpinRite does. SpinRite does not do ANY file system recovery at all. It is a disk media utility... it reads the disk an the lowest level it can, repeatedly, until it either gets the data or fails to get the data. If the disk is returning read errors then SpinRite might be able to help the disk fix the problem by forcing it to work harder.

In any case, SpinRite is NOT recovery software, in the sense most people think of that topic. It doesn't fix file system errors, so if you deleted a file, it will remain deleted. What it might do, is allow the file system to again be able to read a bad sector that was part of the metadata that had been preventing you from accessing your file/directory.

So, depending on the type of error your disk suffers from, depends on what you should do. Ideally, you have backups, or the disk is not in such a bad shape you feel okay pressuring it to do a backup first. If the problem were mechanical in nature, it could be that the problem will spread (say a head crashed originally and now it damages the surface as it tries to read it.)
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As @PHolder says, you might want to backup what you can. You'll probably have to tell the backup software to ignore read errors. If you run CHKDISK with the option to fix errors turned on, it will orphan any files it cannot read. IE you'll get a glob of data with a name such as FILE000.CHK or something. This may or may not be one actual file. This makes data recovery harder. After doing a backup if you choose, I'd run CHKDISK from Windows, but with a caveat. If, in file explorer, you right click on a drive, then properties, then tools, you can check the disk for errors there. BUT, there's a box that pops up where you can turn "fix errors" on or off. Turn that OFF. Also, the "check surface for errors" should be off. (Note I have Windows 7. Not sure about Windows 10 or 11.) Then, if the CHKDISK passes, that's a good sign. If not it may mean the damage to the data is greater. Either way, it won't try to "fix" it. Make note of the results. Then, run Spinrite on Level 2. Make sure the computer has reliable power and preferably backup power. Spinrite will try to recover and rewrite sectors that cannot be read reliably. If storms come up or you suspect power glitches, pause Spinrite and continue later. It may hang up and thrash the drive for a long time when it gets to a bad sector. Just let it run. It might take days. Hopefully, it will be able to recover what's damaged. When it's all done, boot back up and see if your files are readable. Do a CHKDISK again without fixing errors and see if it passes. If CHKDISK doesn't pass and you're files are still unreadable, you could query the people here for more techniques. As a last resort, you can have CHKDISK forcibly fix the file system errors. Then, you'd have to look at those orphaned files and try to determine if there's any recoverable data in them. After all that, I'd run a Spinrite cycle on Level 4. That reads, inverts, writes, reads, inverts, writes all the data on the disk, which should make sure all sectors are usable or reallocate any that aren't. Spinrite's SMART screen may be able to show that. If not, there are a number of disk utilities that can monitor reallocated sectors. I've used Crystal Disk Info in the past. If reallocated sectors start climbing, or the drive is making unusual mechanical noises, grinding, screeching, clicking, consider decommissioning the drive after getting data off. Hope this helps.

May your bits be stable and your interfaces be fast. :cool: Ron
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Pholder: Fair enough. My backup is only a partial one, sadly, so I'd like to rescue as many of the other files as I can.

The disk is misbehaving/compromised in some way for sure, such that I cannot access the files stored on it in Windows. I would be thrilled if SpinRite can cajole it into a better state such that Windows will allow me to read the files long enough to copy them onto other media. Losing some files is acceptable - and, at this point, expected...

rfrazier: Thanks so much for the detailed advice! I'll give it a try
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I would argue AGAINST running CHKDSK before Spinrite. Spinrite will try to recover the data from any failing sectors, whereas CHKDSK will note that the sector is bad, and mark it as such, thus preventing Spinrite from doing any work on that sector.

As you already own Spinrite, you will get better results by running Spinrite first to get any recoverable data back, and then running CHKDSK to verify the file indices and MFT.
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I would argue AGAINST running CHKDSK before Spinrite. Spinrite will try to recover the data from any failing sectors, whereas CHKDSK will note that the sector is bad, and mark it as such, thus preventing Spinrite from doing any work on that sector.

As you already own Spinrite, you will get better results by running Spinrite first to get any recoverable data back, and then running CHKDSK to verify the file indices and MFT.
Thanks, I appreciate the advice. Perhaps I dodged a bullet because CHKDSK was unable to operate on the drive. I mounted the drive read-only in linux and was lucky enough to get a listing of the files, but anything deeper then that (such as copying files) was practically not possible. I seem to be able to mount the drive, then shortly after it loses its marbles. A backup utility failed to copy any files after initially identifying the many existing subdirs/files and ended up in an infinite loop.

I am thinking of running a Level 1 SpinRite scan next, before moving on to Level 2. Before trying the read/write operation of Level 2 I'd like some proof that the drive is robust enough to withstand Level 2 queries. Maybe I'm being silly?
Sounds like the filesystem is unhealthy. SpinRite may not identify any problems at all if that's the case. (In that it's all logical level corruption, and not media level.) Only one way to find out for sure at this point... I don't think you have anything to lose but your data, and that may have already happened. Do a level 2 pass, and hope for the best.
I guess is should also be mentioned, that SpinRite 6.0 doesn't work on very large disks (greater than about 2TB) or on PCs that don't support legacy booting. Have you yet verified that SpinRite will even boot and detect your faulty drive?