silver22

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, 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.

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.

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.

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.