System restore
Right-click the computer and select Properties. On the right, select System Protection and System Recovery. Follow the steps.
Backup image
Win7 system can also use the backup image function, just open the control panel/system and security/backup and recovery/select the left side to create a system image/follow the steps and requirements.
Full backup
It is recommended to download "One-click GHOST 20 16.092. 16 Hard Disk Edition" for installation, backup and recovery, which is very convenient with one click (please search, download and install).
Pre-installed genuine system
It is suggested that consulting brand customer service will tell you the method, because different brands have different methods.
Reinstall (a computer) system.
If your computer crashes with a blue screen and can't boot, the recovery method is basically ineffective and needs to be reinstalled. If you are talking about reinstalling the system, you can't install it yourself. I suggest you spend 30 yuan to repair the computer and install it. If you have any questions, ask me.