Master File Table Records on free space erase

jberaser

Member
I want to erase the free space on my hard drive, but I don't understand the part in the dialogue about that including Master File Table Records. That sounds to me like it will erase a master file that perhaps my other, non-erased stuff (the stuff on the non-free space area) might need.

Is it safe to use this option without causing problems for all the programs, etc., still on the hard drive?

Regards,

JB
 

Robbie

Member
it's perfectly safe. This is from the Eraser Help File: (after explaining about the Free Space Wipe)

If you are running Windows NT or 2000 and the file system on the drive is NTFS, Eraser will next overwrite the free space on the Master File Table (MFT). The reason why this is done is that on NTFS file system, clusters are not necessarily allocated for files smaller than the size of a MFT record, but the file is stored completely in the MFT (the file is then said to be resident). If you have insecurely deleted such a small file, the free space on the MFT still may contain the file body and therefore, it must be erased as well. Windows 9x does not support NTFS file system so this step will be skipped.

Finally, the names of all previously deleted (or erased) files will be overwritten. On FAT{12,16,32} partitions this is done by going through all directory entries and overwriting deleted file entries. On NTFS partitions (Windows NT and 2000 only), Eraser creates maximum length files until the unused entries in the Master File Table are overwritten.



Although this refers to Windows NT and 2000 it includes XP and Vista.
 

jberaser

Member
Robbie said:
it's perfectly safe. This is from the Eraser Help File: (after explaining about the Free Space Wipe)

If you are running Windows NT or 2000 and the file system on the drive is NTFS, Eraser will next overwrite the free space on the Master File Table (MFT). The reason why this is done is that on NTFS file system, clusters are not necessarily allocated for files smaller than the size of a MFT record, but the file is stored completely in the MFT (the file is then said to be resident). If you have insecurely deleted such a small file, the free space on the MFT still may contain the file body and therefore, it must be erased as well. Windows 9x does not support NTFS file system so this step will be skipped.

Finally, the names of all previously deleted (or erased) files will be overwritten. On FAT{12,16,32} partitions this is done by going through all directory entries and overwriting deleted file entries. On NTFS partitions (Windows NT and 2000 only), Eraser creates maximum length files until the unused entries in the Master File Table are overwritten.

Although this refers to Windows NT and 2000 it includes XP and Vista.
Thanks for the response. I'm relatively software and computer literate but when it comes to stuff like the MFT I'm in the dark :) Now that I know it's safe I'll run it when time permits.

One more question if I might. When erasing files or folders I use the 35 pass method, which of course can take some time if the folder contains many large files. For example, a 1 gb folder can take an hour or more. What happens when erasing free space? I would expect only cluster tips and MFT stuff to actually contain info, but if I run the 35 pass on, say, a drive that has 60gb of free space, can I expect that to take 60 hours or more?

Regards,

JoeB
 

jberaser

Member
P.S. to my reply to you. Paul Lepkowski posted a thread on Sept. 15, subject Eraser may have messed up a dll.

That's the sort of thing that worries me. I think I'll wait until I see some knowledgeable responses to his post before I take a chance with erasing free disc space.

Regards,

JB
 

Robbie

Member
jberaser said:
P.S. to my reply to you. Paul Lepkowski posted a thread on Sept. 15, subject Eraser may have messed up a dll.

That's the sort of thing that worries me. I think I'll wait until I see some knowledgeable responses to his post before I take a chance with erasing free disc space.

Regards,

JB
have a look at the reply I've given in that thread. it's (I suspect) a Windows problem that simply requires the user to reboot Windows after running Eraser. The problem certainly sounds identical.
 

Robbie

Member
I've answered your other query in your other thread re: running times for a free space wipe.
 
Top