Windows storage spaces data missing for no reason

Hi, given the anomalies, whilst you say there's no physical damage- I assume you've run some kind of disk check- I suggest you get a copy of Hard Disk Sentinel (SSDs too) - trial- and run that. Best instant appraisal right on its GUI I know of.

Click the tab for each disk to see the report.

That's a good start. It seems you're not alone:
https://answers.microsoft.com/en-us/...3-9d0485888c3d

We see regular reports of this disparity. A more reliable place to check is File Explorer, Disk Management or if you want a graphical view install TreeSize

(I like Wiztree, also free - rather similar).

These can give a usefully different view to that offered by file explorer. But no direct resolution..

However, that still leaves the question of the apparrently missing/inaccessible files..

Windirstat is not maintained and can give an obscure result in 1 case. Wiztree is maintained and receives updates. I believe Treesize is similar in that respect.

Unfortunately I think few here actually use Storage Spaces

dalchina, just a wild idea, if someone is using any sort of anti-ransomware utility, and that utility is in control of designated folders and files, would those folders and files be "invisible" to normal file managers like Windows Explorer? I ask because a long time ago I tried an anti-crytoWhatever utility - which totally hid my user profile from view; thankfully I had a recent backup, which I restored and life went on as normal.

Well, potentially a 3rd party utility with due authorisation could do pretty much anything, I suppose.. your experience is interesting and a great reason for routine and regular backups/disk imaging etc.

I did run one of those a long time ago, but without any adverse effect. I'd certainly be very discontented with such a program that hid my files from me.

As to kaigott's problem of disappearing files, assuming the file system and physical disks are intact and robust, one possibility is of some kind of effect due to a program and in particular malware.

@kaigott - have you tried running a program such as Recuva to see if your missing files exist in some way on disk? As you presumably know the location of these, you can limit the scan. That said, I've never seen Recuva run on a Storage Space configuration.

folders and files are disappearing.

I can't recall seeing anything like this before, although various issues related to Storage Spaces have been reported.

Recovery
One difficulty could be this:

Storage Spaces uses a proprietary form of software RAID and so I found that all conventional approaches to recovery were useless.

You could try this trial software:
Storage Pool: How to recover data from Windows 10 Storage Space?

There is expensive data recovery software available to support Storage Spaces, suggesting a difficulty here. One person suggested these had been found helpful with S. Spaces:
ReclaiMe Storage Spaces Recovery Software
R-Studio Help - Introduction to R-Studio
and there's this:
Effortless data recovery from complex RAID

http://www.storage-spaces-recovery.c...ery-manual.pdf

In addition, if Storage Spaces metadata is severely damaged,the entire pools or spaces may be missing.

- note the reliance on metadata.

Metadata
Storage spaces use metadata. I haven't yet found quite how or what this is used for, but it's another possible vulnerability.
https://docs.microsoft.com/en-us/win...-spaces-states

This gives a variety of Powershell commands some of which you might use to interrogate your Storage Space to determine more about its status.

Configurations: which of these 3 configurations is yours?
How to Use Windows 10’s Storage Spaces to Mirror and Combine Drives

Are you using NTFS or ReFS?

The most basis seems to be simple, and NTFS- whilst the others provide some protection and resiliency.

I think elementary drive failure has been pretty much ruled out.

Bottom Line
A few people who've used this and had problems have vowed 'never again'.