SDelete is a Vital utility to any Windows. Ironically, only about 1% of Microsoft Windows Users even know about SDelete.
Microsoft decided long ago, that it was “better” to remove only a files entry in the MFT (Master File Table) when a file is “deleted”, rather than actually removing the file, by over-writing it with Zeros.
So basically. In Windows, when a file is deleted, the file is still there. Yes even if You “permanently delete” from the Recycle Bin, it is still there.
This creates 2 Problems.
- User data can be “mined” from the system when the OS is not in control. Think data recovery Software, and “undelete” Apps.
- Software outside the OS, CANNOT correctly distinguish free space from data after a certain amount of files have been created/deleted. Think guest file system inside a virtual machine.
Regardless of the which reason, SDelete is Your friend.
In the Example below I have downloaded SDelete from Here<—– Official Microsoft Technet site.
Now extract the contents of the Zip file directly to the C:\ Drive.
SDelete does not have a gui, so You will have to use an Old School Command Prompt. Start–>Run—>Type “command”—->Hit Enter
If You are using Sdelete for virtual disk image optimization, simply run the following command “sdelete -z c:” without the quotes.
This will make 1 pass (-p 1) and write Zeros to all the free space (-z) on drive C:\
If You want Sdelete to securely erase “free” space after deleting files, run the following command. “sdelete -c -p 1 c:” Once again without the quotes.
Once You hit enter, Have a doughnut they are good.
NOTE: This process can be painfully slow on the following:
- Huge Raid arrays
- Slow Hard drives USB HDD, Laptop HDD, older Pen Drives
- Virtual machines
- If You used the -c option.
- Grandma’s Old E-Machine
Once SDelete has done its thing, You should see something similar to the message below.