Search for DBAN on Sourceforge, a solution which will completely erase your hard disk.

Otherwise you need something like eraser to wipe out free space on your windows disk.

Hi, try the following URL (http://www.oo-software.com/home/en/products/oosafeerase/).

Qoute: "O&O SafeErase 3 is THE solution for the secure deletion of sensitive data from your hard disk and offers you the ultimate protection of your private sphere. With just one click of the mouse you can securely and permanently delete files, folders and partitions.

The motives for the deletion of files are many".

I liek O&O so download trial version (not sure what teh limits are for trial but it will tell you when you use it).

The only way you can be sure is to give them a fresh HD or no HD at all. It is possible to recover upto 32 layers of deleted data if you have the right tools but you have to ask yourself what kind of damage could actually be done with the information on there. Personally if I were you I'd probably just format and reinstall windows

Like Dale says, I'd just reload Windows, only with a fresh partitioning as well. Especially if you're giving the PC to someone else, a fresh install will be better for them. If you're really worried about the data, keep the disk.

You could try one of the following software products that erase personal info from the hard drive

Migo DriveWasher

Paragon Disk Wiper 8.5

PCSecurityShield WinShredder 2

Good manufacturers provide software for this, usually in bootable form.

Don't be one of these fools who sells their PC with no hard drive, throwing money away.

i've been doing this for years, use a bulk tape de-magnetizer and zap your hard drive, then format and re-install your system files. simple and effective.

Don't bother with any of those crazy bought solutions. Simply avail yourself of a Linux bootdisk distribution (such as Tom's Root Boot for a floppy, or knoppix for a CD). After booting up the floppy/CD and logging in, type:

dd if=/dev/zero of=/dev/hda

and wait until it finishes. Replace hda with sda for SATA disks.

The contents will, in my opinion, be erased sufficiently well as to be effectively unrecoverable by most people likely to come across your old computer.

Repartition and reinstall an OS if you choose to.

If you're using XP and NTFS, use EFS to encrypt your disk. http://support.microsoft.com/kb/307877

Or you can use TrueCrypt for Win 2k/XP/Vista and it doesn't matter what format your disk is in: http://www.truecrypt.org/