How do you permanently delete files from computer?

My contacts in the military tell me they always use BCWipe to permanently delete files. Some even say that BCWipe is such a powerful and effective tool to completely wipe data, that they won't allow other staff to keep the software on their computer. For many years, I've relied on BCWipe to be 100% certain that my private data cannot be recovered. And it's actually very simple to install and start using in minutes.

http://www.jetico.com/wiping-bcwipe/

There's simply no better way to permanently delete files.

Left click to select the file, then just press the delete key. It is true that this doesn't remove the file from the hard drive, but it does take down the "fence" that protects it, so it can be overwritten. Make sure you empty the recycle bin afterwards - to do this, right click on the Recycle Bin icon, then select 'Empty Recycle Bin.'

Reformatting or a program like Window Washer, and several free programs similar to it, will make them inaccessible. There are several programs available that will overwrite those files multiple times, to ensure that they are not retrievable. Norton security suite has one, I think. There are others, some free.

Use HDCleaner, it will overwrite n-times any file so it won't be found even using recovery software, I've tried it and it really works, this is the solution for those of us leasing software; this app will erase the blank space in your hard drive, too. Yep, it's free. Good Luck!

There are many freeware software available to permanently delete files from Hard disk. These software follows one of many wiping schemes as explained in http://www.globinch.com and they mentioned SDelete from sysinternals as a free utility. The effectiveness of wiping programs depends on how many times (pass) it is overoverwritten.

Another one is "File Shredder".Advantage is it's right click context menu which makes it very convenient.

http://www.skipser.toolsbysk.com/p/2/p/how-to-securely-delete-files-permanently-from-your-computer.html