Have you ever lost a file on your computer?
Important files from one operating system components.
Or conditions where there are "windows file system error".
The following information you can use for error conditions missing windows file system.
1. Shut down all running programs
2. Open a cmd / command prompt (black box background)
3. Right click, run as administrator
4. Select yes to notifications UAC [User Account Control]
5. Type the command sfc / scannow
7. Restart the computer
NB: This method has been tested on a laptop friends while experiencing an event like this, and proved to be.