Windows 10 OS drive: how is 40GB of space missing! (111GB drive, so it's significant)

mike7877 · Jul 25, 2023

tl;dr Where can I find out what's taking up this space.

Pictured below is one of my PCs' OS drive. The size of the selected grey folders is to the right in the Properties dialogue box. 71.6GB, size one disk 70.9GB (wait a sec... isn't size on disk usually larger than size?... anyway...).
Below OS drive contents I pasted a snip of Local Disk (C

as it appears in explorer, in "This PC". 3GB of 111 is remaining.

Almost 40GB is unaccounted for. I've done disk cleanup, I've tried cleaning system files - "previous Windows versions", and things like "previous Windows Updates" weren't taking up any space at all.

You can see in the bottom left corner that the recycle bin is indeed empty...

I just don't get what's taking up all this space!

I don't want to reload this machine for many reasons - most simply put: it wouldn't be easy.

Is there a way to find out where this phantom 40GB is hiding?

edit: Technically it's 34.78GB is unaccounted for when the total size on disk of all folders in C are totaled - Program data is 1.73GB, and $WinREAgent is 0 bytes - the rest of sizes are in the picture and the text above.

Paradigm Shifter · Jul 25, 2023

Size of pagefile and hiberfil.sys?

If you have anything installed via MS Store, they are often installed in directories which will report they are zero bytes, despite containing 100GB+ of data (Forza Horizon 4 and 5 do this)...

Tqhr · Jul 25, 2023

mike7877 said:
tl;dr Where can I find out what's taking up this space.

Pictured below is one of my PCs' OS drive. The size of the selected grey folders is to the right in the Properties dialogue box. 71.6GB, size one disk 70.9GB (wait a sec... isn't size on disk usually larger than size?... anyway...).
Below OS drive contents I pasted a snip of Local Disk (C as it appears in explorer, in "This PC". 3GB of 111 is remaining.

Almost 40GB is unaccounted for. I've done disk cleanup, I've tried cleaning system files - "previous Windows versions", and things like "previous Windows Updates" weren't taking up any space at all.

You can see in the bottom left corner that the recycle bin is indeed empty...

I just don't get what's taking up all this space!

I don't want to reload this machine for many reasons - most simply put: it wouldn't be easy.

Is there a way to find out where this phantom 40GB is hiding?

edit: Technically it's 34.78GB is unaccounted for when the total size on disk of all folders in C are totaled - Program data is 1.73GB, and $WinREAgent is 0 bytes - the rest of sizes are in the picture and the text above.

View attachment 2622138

WinDirStat - Windows Directory Statistics best program to use for this exact situation

Tom5051 · Jul 25, 2023

have you run disk cleanup with windows update checked? probably the winsxs folder out of control

Neutronman · Jul 25, 2023

May be easier to diagnose if you take a look in Computer Management--->Disk management. See attached.
Check for any unallocated space.

.667270 · Jul 25, 2023

i use disk cleaner (run as admin) then run bleachbit.
like stated above hibernate file could be big well over 10gb. also mentioned above windirstat breaks things down nicely according to size to see whats sucking up space.

azanimefan · Jul 25, 2023

check your system restore; windows and disk space checking software like windrisys don't see the system restore sector of your drive. i've seen system restore when configured wrong eat up huge chunks of an OS drive's space before.

Relevant Wing · Jul 25, 2023

Check your page file size.

mike7877 · Jul 25, 2023

Tom5051 said:
have you run disk cleanup with windows update checked? probably the winsxs folder out of control

Yeah, that's the first thing I did

mike7877 · Jul 25, 2023

Paradigm Shifter said:
Size of pagefile and hiberfil.sys?

If you have anything installed via MS Store, they are often installed in directories which will report they are zero bytes, despite containing 100GB+ of data (Forza Horizon 4 and 5 do this)...

Rectangle Screenshot Font Parallel Software

Automatically managed by OS

Also nothing's installed through their store

Relevant Wing said:
Check your page file size.

Auto manage paging file size

mike7877 · Jul 25, 2023

azanimefan said:
check your system restore; windows and disk space checking software like windrisys don't see the system restore sector of your drive. i've seen system restore when configured wrong eat up huge chunks of an OS drive's space before.

System restore is 4.45GB

mike7877 · Jul 25, 2023

Tqhr said:
WinDirStat - Windows Directory Statistics best program to use for this exact situation

Since everything I can check without installing anything looks good, it's time!
I've heard of this.. it's been around for a while, right? And it's very good?

edit: yeah, I've used this in the past - I remember the beautiful graphical representation of all the files
For those who don't know, all files on the drive are represented by boxes which vary in size. If the file takes up 1.3% of your drive space, the box takes up 1.3% of the space representing your drive! You can click the file and it takes you to the folder containing it. So awesome!
Just be careful not to delete anything important of course, because you can do that.

mike7877 · Jul 25, 2023

Ah, Hibernation is enabled - 6.4GB...
I find Hibernation annoying for everything except on laptops to save dying batteries' standby sessions.

Eliminated! Hibernation just seems stupid to me - to maintain peak performance a reboot should be done daily, so why...

And...

As long as the page file isn't counted when selecting those grey folders in my picture in my OP (Program Files, Program Files x86, Users, Windows), then 5.5GB (not 4?!) has also been eliminated!

Just short of 12GB of just short of 35GB has now been recovered.
Just tall of a third of the phantom has been uncovered (lol) Discovered*

Atekk920 · Jul 25, 2023

use a free program like wiztree and it should tell you in a matter of seconds exactly what is eating all that space. I'm guessing a hibernation or page file?

Somasonic · Jul 25, 2023

TreeSize Free is also pretty good for this sort of thing.

Trys0meM0re · Jul 26, 2023

Somasonic said:
TreeSize Free is also pretty good for this sort of thing.

This one is great, another similar program, that is very good is Windirstat: WinDirStat - Windows Directory Statistics

zzztopzzz · Jul 26, 2023

From run select CMD (as Admin) then enter DISPART ?.

From there you will be able to look at all of your disks and partitions and do maintenance as required.

Atekk920 · Jul 28, 2023

Trys0meM0re said:
This one is great, another similar program, that is very good is Windirstat: WinDirStat - Windows Directory Statistics

Bro - your signature has me dying over here! Facts! 🤣

Windows 10 OS drive: how is 40GB of space missing! (111GB drive, so it's significant)

mike7877

Paradigm Shifter

Tqhr

Tom5051

Neutronman

Attachments

.667270

azanimefan

Relevant Wing

mike7877

mike7877

mike7877

mike7877

mike7877

Atekk920

Somasonic

Trys0meM0re

zzztopzzz

Atekk920

Top Contributors this Month

Recommended Communities