I take it you don't have a backup. One thing you can do is download Windows 10 from here:
http://www.microsoft.com/en-us/software-download/windows10 . Then burn the ISO file to a DVD and boot from it.
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When you've gotten your system back like you want it, I urge you to get yourself an external hard drive and a good 3rd party backup program. You can set it up to do everything automagically at the time and frequency of your choice. 1 TB external hard drives are about $50 these days and a really good FREE backup program is the Easeus Todo Backup Free. That can save you a lot of time and frustration the next time something like this happens. Sooner or later it happens to all computers for one reason or another.
Good luck.
I am using windows 7 ultimate and i have downloaded win10 but after installing , screen went black .
I googled and found that i should remove the power plug and battery and it would work fine but when i did that a screen appeared with win10 logo and says (restoring previous windows files)
I waited and windows 7 returned back .
Finally, I have known that my antivirus was the cause of this issue,especially because i was enabling the aggressive mode which stops any change in system files.
I want to reinstall win10 but the win10 icon in taskbar disappears and the windows 10 media tool requires boot disk because of the clean install that will be done . I wonder if the issue was in the graphics that doesn't satisfy win10 as many told me,what if the story was repeated ,I wont be able to get win10 and couldnt return to win7 . So,What should I do?
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