Deletes the system file by mistake, flies the letter not to be able to open

I was not careful delete some system files, the system have endured the return to original state, the rewiring flew the letter N time not to be good, fly the letter not to be able to open, spring a dialog box saying:“Fetion 2008 meet the question to need to close.We cause regarding this express the regret inconveniently.”Installed .NET framework not to be good
Ask how to solve this problem Question supplement:ICQ and so on other normal, is flies the letter not to be able to open

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