How do I recover files from my computer's hard drive after they have been completely erased?

Recently in the company and the new company to do the handover of work, waited for one months, finally a new colleague to take over this piece of work, to tell the truth, although the boss gave me a little more pay, but a person to do two people's things, or very tired, I have not remember this month I added how many night class, Just think every night is very tired, lying in bed every day can fall asleep in minutes, but there is no way, after all the boss confessed things, we still have to do well.
And this time, my computer's files are also a great increase, because another job is a management data work, so often need to save files and so on, and then need to upload the release, very troublesome. This is not, yesterday I suddenly all packed to a new colleague, then began to clean up the files in their own computer, anyway, this will not be my work again, should not need to use it again, and then delete the time, the computer is too large, need to delete, I still chose to determine, so, File completely disappeared in my hard drive, but depressed is, the new colleague but told me to receive the files in the compressed package is garbled, sweat, how to do? The original file has been deleted by me!

In the end I found on the internet this is called invincible HDD recovery software tool, this software is very good, not only powerful, operation is also very convenient, simple three or four steps, simple set up a few paths, the software can automatically operate. It took 20 minutes to get the missing files back.
Data recovery software cracked version: http://www.ddooo.com/softdown/50284.htm

How do I recover files from my computer's hard drive after they have been completely erased?