Teach you to find the safe mode under F8 in Win8

In Win8 we will not be able to enter the safe mode by pressing the F8 key under power-on, which is limited by Win8's new secure boot mechanism. If you want to enter safe mode by pressing F8 at boot, you can do this by following the steps below.
How to retrieve the security mode under F8 in Win8: Start the command prompt as an administrator

Enter
bcdedit /set {default} bootmenupolicy legacy< in the open command prompt window Br>
Enter to confirm. After performing this operation, restart the computer and press the F8 key to see the traditional advanced startup options.

If you want to return to the Windows 8 default startup mode, you can do so by entering the following command.
bcdedit /set {default} bootmenupolicy standard