Is here someone who can help me to solve the computer problem

How cheesed today is. There were something wrong with my computer in the last few days. It could not connet  to a network. I tried many methods to work out the problem . There is no way to solve the problem all the time. My boss is a an irritating man,he critisized me severely bacause I slowed down my work .But it was not my wrong mistake ,i didn't know what happened to my computer. Even though he found a computer repairman technician to repair it yesterday, it still couldn't work normally. So i suggested maybe we could reset the system. He agreed finally. But just in case, i told him the risk about reseting, we may loss some important files ,so we should copy or divert them to disk D or another storage first. My boss just said 'Solve it quickly'. But unfortunately, i forgot to make an e-mail copy after i finished reseting. You know, the orginal outlook files were saved in disk C, but now it has been formated. Is here anybody know how to recover the data? Thanks for your help.