Erasing Free Space
Posted 03 September 2012 - 03:21 AM
Posted 03 September 2012 - 06:28 AM
UNLESS that data has already been deleted and thus placed in free space.
I do not know what trace vestiges of deleted data may escape the attention of a Free Space and MFT erase.
I will leave it for those with more experience to advise you.
I will however point out that these "trace vestiges of deleted data" are only accessible to some-one with control of your computer,
such as a thief or a VAT / TAX inspector ( if there is a difference ),
and will not be made available to the internet unless your computer is taken over,
in which case your current live files will be the prime focus;
the hacker would not be installing and running Recuva to extract remnants of last year's files.
For business continuity you need to have a backup system in place.
I use partition imaging backup software that makes backups to an external hard drive,
If my internal drives crash or burn then I can buy new drives and my Rescue Boot CD plus the external drive make everything good again.
I use Macrium Reflect for backups.
By DEFAULT it uses "intelligent copy" that only captures files which have NOT been deleted, and excludes all of Free Space.
This CAN alternatively perform a "forensic" backup that will capture all your files,
PLUS (not what you want) everything else that is within Free Space including all the files you deleted without erasing.
Macrium can restore all partitions and their contents to an erased HDD or a brand new HDD.
Windows 7 includes a built in image backup capability that should restore contents to partitions,
and may even (for all I know) have the ability to restore a missing partition.
Macrium and alternative third party image backups have user benefits over the Windows 7 capability.
Special benefits of Macrium include :-
Excellent support by the developers ;
Very reliable restoration.
It is always good to test the restoration capability of any backup utility BEFORE you depend upon it.
A significant number of people have found that Windows 7 built-in capability has let them down.
If you have a tested and proven backup/restoration capability,
and if you remain concerned about anything remaining after Erasing Free Space and MFT,
then use something like Macrium intelligent copy to backup onto external HDD,
then use the Boot Rescue CD to validate the external HDD backup file,
Then erase your internal HDD,
and then use the Boot Rescue CD to restore the internal HDD from the external HDD
n.b. CCleaner runs under Windows and is not able to wipe the HDD that holds Windows.
You can use something like
It would be advisable to safely disconnect the External HDD BEFORE you launch DBAN
because that site states
To segregate your personal shopping and business activities you could use two separate browsers, such as Opera and Firefox.
Technically, for greater segregation you could create a new partition or buy an extra HDD,
and either use a virtual machine or Dual Boot to select which instance of Windows you are running.
This may have license implications.
I am not able to give further advise on this, but others may.
Posted 03 September 2012 - 07:40 AM
Posted 03 September 2012 - 08:57 AM
All documents and personal files and all of Windows which were NOT deleted would NOT have been erased.
SOME of what was NOT deleted will have been over-written when you reloaded Windows,
BUT some would remain and can still be retrieved unless you again erase free space etc.
I strongly recommend that you erase free space etc. again just to be safe.
An employee may be restricted in what he can do via a Guest account.
Your dangers :-
He may plug in a CD or a Flash Drive which gives him full control and even greater access than Windows allows you as an administrator :
He can steal, copy, use, publish passwords and confidential information ,
and plant malware which detects whether he is still on the payroll, and takes action when he is removed.
Even a trusted employee may take vengeance if he does not get the pay rise or promotion he thinks he deserves.
It might be wise to buy a cheap second hand laptop, perhaps running XP, for access and use by the employees.
Posted 03 September 2012 - 05:19 PM
But the one you just installed is the only one that will load. A bit weird, as this seems to "escape" a format, but it can be edited out via right-click my computer/properties & going into the startup options & edit/save. This does lead me to wonder what file(s) (if any) escape formatting a drive, as well as if a file is located in the same directory as before with the same name, would it cause prior "erased" files (or registry keys) to become visible again?
I would think that the safest way is to disconnect the drive you use for your OS, format & wipe it externally via external USB cabling, then re-connect & install Windows if you so desire.
If still in doubt, heating it in an oven to 1,500 degrees for 3 hours should do the trick as high temps tend to destroy magnetism.
Just be sure you only do this to a drive you never intend to use again.
Posted 03 September 2012 - 07:39 PM
Posted 03 September 2012 - 10:35 PM
Posted 06 September 2012 - 08:44 PM
Posted 07 September 2012 - 01:40 AM
This will securely delete (i.e. overwrite) live files. Any previously deleted files will not be overwritten. Also depending on what's being run on the pc at the time some files may be locked by other processes and not be deleted.
I then reinstalled windows 7 which overwrote the previous version.
This will not normally overwrite any old files apart from those few directly overwritten by system files during the install. I understand that in Win7 (I'm not a W7 user) there is an extended format option (the slower option) that will overwrite the partition with zeroes before the install. I don't know if you did a format or not, but this looks like a good option.
Then I did a 3x overite plus mft of my free space.
If you did this immediately after the format then you should be pretty sure that all you old data has gone.
Could a normal employee not a nasa employee recover my previous browsing sessions?
Nobody here can give a definite answer, but I would say that you're pretty safe.