Win7 system boot black screen appears code "Windows can not start" how to do

The cause of the failure: The actual code means that the boot file is lost. The boot file (NTLDR) is usually stored in the root directory of the C drive. It is a system file with hidden and read-only attributes. The primary responsibility of the boot file is to resolve the Boot.ini file. The win7 system will undergo three stages of pre-booting, booting, and loading the kernel during the boot process. If there is a problem in one of the phases, the system will not boot properly, resulting in a black screen on the computer.

Solution:
1, when the Windows7 boot disk into the floppy drive, or Windows7 system installation CD into the CD-ROM drive, restart your computer;
2, when the "Welcome When installing the Programs screen, press the R key to start the Recovery Console;
3. At the Recovery Console command prompt, type the following lines of commands and press Enter after each line of command input;
md tmp
copy c:windowssystem32configsystem c:windowstmpsystem.bak
copy c:windowssystem32configsoftware c:windowstmpsoftware.bak
copy c:windowssystem32configsam c:windowstmpsam.bak
copy c:windowssystem32configsecurity c:windowstmpsecurity. Bak
copy c:windowssystem32configdefault c:windowstmpdefault.bak
delete c:windowssystem32configsystem
delete c:windowssystem32configsoftware
delete c:windowssystem32configsam
delete c:windowssystem32configsecurity
delete c:windowssystem32configdefault
copy c:windowsrepairsystem c:windowssy Stem32configsystem
copy c:windowsrepairsoftware c:windowssystem32configsoftware
copy c:windowsrepairsam c:windowssystem32configsam
copy c:windowsrepairsecurity c:windowssystem32configsecurity