Unknown Hard Disk Space

[silver22]

Bonjour,

Could someone explain me where big <unknow> HDD disk space comes from ??

<Unknown> is the difference: Total HDD capacity minus free space minus determined sum of the sizes of all files . This rest could be directories or others with read-access denied !!!

They are not hidden files, but seems just space reserved by programs.

Are they linked to "system restore points" ? I don't know, as I understood that these restore points were included inside "hiberfile" file, which is counted in the sum of files, so it' strange;

in my example:

On partition C:\ with Windows Xp and programs:

HDD partition C: total capacity : 96 GB

Free Space: 81 GB

Used Space by all files: 10,4 GB

So, <UNKNOWN> is 4,6 GB ............... very big for just 10,4 GB used.

The same principle is also on partition D:\ , giving 3,6 GB <UNKNOWN>.

Question:

Is there a possibility ( windows command or other ) to identify which is ( are ) using or have reserved this space on the HDD ???

or is there a small utility program to do it ?

If this is the space reserved for sytem restore points,

Is there a mean to display it ??

Thanks for your help.

[boooggy]

u can use partition magic to see watt up with that space. is not use by system restore.

[silver22]

I was not aware about this from partition magic, I thought that it was just to create, manage, etc. partitions, but not to identify space on HDD.

[purewaveform]

check the system restore directory. usually this is where people are missing a couple of gig. also use tools that can read it, search for supershell on this forum,) i already posted it once) it will allow you to be nt/authority in a command prompt, then you can cd into any directory and do a dir /s to get the proper size.

[Takeshi]

Windows XP recognises SR so it shouldn't report the space occupied by the SVI folder as UNKNOWN. They are all accounted for in my system.

SR points are totally separate from hiberfils file.

It's easy to dip into the SVI folder without using extra tools.

With it unhidden and Simple File Sharing disabled, R click on System Volume Information folder > Sharing and Security > add your admin account to the list. Ensure there is at least Read permission.

Then you can read how much space is taken up in Explorer directly.

[silver22]

Windows XP recognises SR so it shouldn't report the space occupied by the SVI folder as UNKNOWN. They are all accounted for in my system.

SR points are totally separate from hiberfils file.

It's easy to dip into the SVI folder without using extra tools.

With it unhidden and Simple File Sharing disabled, R click on System Volume Information folder > Sharing and Security > add your admin account to the list. Ensure there is at least Read permission.

Then you can read how much space is taken up in Explorer directly.

<{POST_SNAPBACK}>

Hello Takeshi,

Note that I Cannot have access to SVI on my home computer ( Windows XP Home Edition) as permission is not available from proprietary of the folder after turned on the hidden system folders ( there is just an option sharing and the other one is about the icone choice for folders; NO security option available ;this "proprietary" menu is the same for all folders,

but I done the same to my job computer running with windows 2K and effectively, it was possible to have access to this SVI folder ( size was 20Ko). Security option exists.

On this computer , I have also <UNKNOWN> space about 150Mo.

I recommend you tu use this small utility program to know if you have also a same <UNKNOWN> HDD space. It is "Windirstat" , free software , but don't forget to turn on the option see "unknown and free spaces" in the menu.

You could find it on the web.

Be waiting more info if you know how have acces to SVI folder on WXP Home Edition and what was the result of your test.

[purewaveform]

sure you can get access to the SVI folder. Just make your user an authority user. Use a program called supershell http://p-nand-q.com/download/supershell.html and then you can get into it just like any other folder.

[Takeshi]

purewaveform: I'll try your suggested program which I saw mentioned on another post.

silver22: I didn't realise you have XP Home Ed, in which case it is not possible to access the Security tab except in Safe Mode. So try the Safe Mode first.

If you are dual booting with Win2k (from what you said), then you should be able to view SVI directly in Win2k.

It's also possible to edit folder security permissions in normal mode using the cacls command (also available in XP Home Ed.). I've tried it successfully but it's rather non user friendly.

I've actually used another small tool before, called DirGraph, which shows graphically the space occupied by directories. But thanks for your suggestion too.

Whatever method you use to view the SVI folder, you should not manually delete the RP subfolders (each corresponds to a restore point) but do this via the System Restore interface.

In fact if you disable SR it will delete all the restore points so it is a quick but indirect way to find out how much space is taken up by SR.

An empty SVI folder (with no SR points at all) should have a size of 20.0 KB.

[silver22]

Takeshi, purewaveform,

Thanks you,

Finally, I used cacls commands to access to SVI and effectively, the UNKNOWN space is well a big file as Restore points.

In order to know why It was so big, I made a simple test by installing a 4 GB game on D:\ partition, not on C:\, then removing it immmediatly; the restore space was checked each time ;

after installation, RS increased by about 200Mo on C and same on D, but the worst was after the game desinstalled, C was up by 100 Mo more and D by 500Mo ,

conclusion: install and desinstall a 4 GB game gives 1 GB more restore space.

I understand why I have about 10 GB "restore points" space ( C+D) reserved on the HDD, for about 10 GB on C and 40 GB on D software installed.

So, the only way to recover this space is to disable SR and removed all restore points, then restart from a Restore point I will do.

I did not see any command to select and remove some old restore points, just space definition is possible.

I will let you know the result.

[tubui]

How can you get data from UNKNOWN partitions? What programs can we use.

[silver22]

How can you get data from UNKNOWN partitions? What programs can we use.

<{POST_SNAPBACK}>

tubui:

Windirstat ( easy to find on the web) gives the unknown space, which is in fact the space taken by Systeme Volume Information, whose access is denied.

this folder is in fact the folder of all restore points.

To have access to the SVI, I followed the process given by Takeshi;

Thanks Takeshi.

first, need to turn on the display of hidden files in files menu tool , to show

the SVI folder, when display the files of partition,

then use the DOS command CACLS to give access to SVI;

you could find on the web the syntax.

for Windows XP Home Edition:

open a cmd windows by doing:

Start, run , then in the windows, type "cmd";

when windows is opened you have:

C:\Documents and Settings\ user ( name of user) >

now, go to the racine of the partition, to be at SVI level.

type:

>CD \ then return

you must have now C:\>

now type the following command to have access to SVI folder:

calcs "partition letter:\protected file name" /E /G username:F

example: for SVI access on partition C given to Juan Peter user, it 's:

cacls "C:\System Volume Information" /E /G "Juan Peter":F

Don't forget the " , as they are used to not take into account the blank between

words.

the same can be done for partition D.

after that the right is then turn on and you could have access to SVI folder and see all restore points files.

I strongly recommend you after to remove this access right by the opposite following command:

cacls "C:\System Volume Information" /E /R "Juan Peter"

then turn off the display of hidden files in files menu tool

in order to come back to normal situation ;

As recommend by Takeshi, don 't delete manually some SR points

because the system could become instable I think, but disable it and all restore points will be removed;

to be done only if you are sur that your system is very stable.

I certainley will try the option to limit the space used for SR points,

as in fact I have currently 160 SR points.

When this limit is changed ( currently 10%),

are the old SR points deleted by the system ??

[Takeshi]

When you reduce the size (space) reserved for SR, it will purge the oldest SR points first until enough SR points are left behind to fit the new size.

I personally find that the default 10% space reserved is far too big for the average user, esp. now most have enormous sized HDs and many have Ghost backups too!

Depending on your needs, I find that limiting the space to about 500 MB (the % will vary depending on the total size of the partition) is enough to hold 3-4 SR points, which to me is more than enough. In the 3 years of using XP, I never need to restore to the SR point older than the last one.

I leave the modified permissions in the SVI folder because I'm the only user but you're right to be cautious about setting the permissions back to SYSTEM only afterwards. I find it's easier for me to check on the size periodically. (Sometimes it exceeds the size you limit to!)

I forgot about MS KB:

http://support.microsoft.com/kb/309531/

[jeffshen]

do you have norton system works installed? would the space be taken up by "Norton Protected Files"? I tried emptying that once and it gave me abck about 5gigs of space on my HD...

J

[falcon2099]

I did not see any command to select and remove some old restore points, just space definition is possible.

With Disk Cleanup (RClick on drive -> properties -> Disk Cleanup button) you may remove all but the LAST restore point. Once the dialog box for the Disk Cleanup opens, click the More Options tab at the top and click the bottom "Clean UP" button for System Restore.

Hope this helps!

[Alanoll]

In fact, access to SVI gives the list of all restore points, with their date; It 's a list of directories including files

and It will be nice if the system could give to user the possibility to delete choosen restore points, but It's not.

we could  manually delete some directories but in this case I think that windows could be instable, as it's not done by the program managing the restauration.

So, I understood that we just have the choice to delete all.

From silver22.

@silver22

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