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Treesize shows unknown folder occupying 55.4% of the drive space.


When I ran Treesize professional 3.0 on a folder in a server drive, it shows about 50% allocated to an unknown subfolder folder, There is no subfolder called "unknown". Where is  this disk space going and how to recover it.

The OS is Windows server 2003.


1 Solution
John HurstBusiness Consultant (Owner)Commented:
Run TreeSize with Run as Administrator. See if that shows you. It is probably System Volume Information, but it could be an orphaned folder of some kind.

Run as Admin, capture the screen shot and post it if you can
Roger38Author Commented:

I ran it as administrator with no restrictions.

But still its shows the same results.

There is no subfolder called "unknown". Where is  this disk space going and how to recover it.

Please see the attached screen shot.


John HurstBusiness Consultant (Owner)Commented:
Hi Roger, the screen shot did not post for some reason. Please try again.

I think you must have an orphaned folder from a failed backup or something like that.
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Roger38Author Commented:
Hi John,

I put it as an attachment as I could put the screen shot in the comments.

There no folder called "unknown"  in windows explorer.

But Treesize indicates that there is an unknown folder.

Please see the attached file.Doc6.docx
John HurstBusiness Consultant (Owner)Commented:
Thank you for that.

It is impossible to say what it is, and Tree Size Admin will show System Volume information.

Things that could cause this:

a. Failed backup.
b. Failed install of Server 2003.
c. Windows Backup creating duplicate backup folders.

Is the any way to get "Unknown" on the left hand side of Tree Size and then expanding it to see what is inside.

In Treesize, the Users tab desginates the file owners. Therefore "Unknown" isn't a directory, but these are all the files from which the owner is unknown.
You can try to reset the owners of all files in your home directory folders with something like
CD Users
for /D %A in (*) do icacls %A /setowner %A /T /C

for /D %A in (*) will enumerate all directories, and perform the commands after "do"  on each directory
icacls %A /setowner will set the owner of all files in a directory to %A
/T will also do subdirectories
/C will continue on errors (errors will be displayed)

Of course this will only work if your home directory names are the same as your user names. You'll probably find some directories which don't have an owner anymore.
Pramod UbheCommented:
have you also tried to enable hidden files and system protected files, then open that folder in explorer?
John HurstBusiness Consultant (Owner)Commented:
Are there user profiles that have been abandoned?  I would not think it take that much space on a drive, but it is worth checking.   You can check profiles in Advanced System Properties.
John HurstBusiness Consultant (Owner)Commented:
@Roger38  - Thank you and I was happy to help.

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