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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