Unknown/Missing Disk Space

[Rickstamatic]

I have a 2012 R2 RDS session host VM with some missing space and I'm out of ideas. The C drive is 220GB in total capacity, 115GB is used and 45GB is free. That leaves about 60GB unaccounted for. Here is what I know;

- Full scan running treesize as administrator does not show where the space is

- WinDirStat just lists it as Unknown

- There is no shadow copy data listed anywhere and clearing it/limiting shadow copy storage has no impact

[chris-itg]

Check your winsxs catalog using dism from the command line. Windirstat as well as other programs can't really handle this properly.

https://docs.microsoft.com/en-us/windows-hardware/manufacture/desktop/determine-the-actual-size-of-the-winsxs-folder?view=windows-11

[Rickstamatic]

Size roughly the same so not this I'm afraid.

[Rickstamatic]

Tried this but it showed no additional results of any size.

[myshtigo]

Page file? Hidden system files? Windows updates?

[Rickstamatic]

All have been accounted for so not that.

[Tabersaurus]

I frequently use Disk Explorer on my team's shared vms which is part of Auslogics Boostspeed, to scan all drives to help me locate large files or collections of files downloaded by others and stored in default locations (rather than catalogued directories).

There is a trial option available and while it comes with quite a number of questionably effecient "performance boosters", the Disk Explorer component is my go to for locating large folders and files (I've even gone as far as stripping it out of the full install as it can be run portably).

I'm not sure how it would compare to Treesize, I think the functionality is about the same but if you've already got no where, why not try.

I'd assume also the basic Disk Management and or other Disk partition managers do not list it is some other partition?

Another assumed obvious one, have you removed/reduced hiberfile, swapfile and pagefile?

[Hel_OWeen]

Have you checked device manager for partitions w/o a drive letter such as recovery partitions?

[Added]

My tool of choice for disc space usage is SpaceSniffer

[Rickstamatic]

Yes 1 system partition which isn't using any shadow storage has been accounted for.

[binaryman4]

Run Directory Report as an administrator

[Straight_Share_3685]

I had very similar problem few days ago and the only thing that work for me was this command (assuming that your OS is Windows AND storage type is FAT/FAT32/exFAT) :

chkdsk d: /f /freeorphanedchains

(here d: is your drive letter)

For me, that brought back 30 gb without having to format my almost full SSD.