Friends who have used Win8 know that because Windows 8.1 uses a mixed-mode fast boot, it is not possible to use F8 into Safe mode, but we can turn off the fast Start feature, otherwise the old version of the F8 into Safe mode functionality.
To enable fast startup off, you can do the following:
1. Press "Win" + "X" shortcut key;
2. Select Power Options from the shortcut menu that appears;
3. Click the "Select the function of the power button" option;
4. Click the "Change current unavailable settings" item;
5. Cancel the quick start and save at the bottom of the interface.
Close the quick start, press the "Win" + "X" shortcut, select the command prompt (Administrator) option on the shortcut menu, and enter "Bcdedit/set {default} Bootmenupolicy legacy" in the English state and return.
The "Operation completed successfully" prompt appears, indicating that you have successfully set up. Reboot the computer and press the F8 key to see if there is a traditional "safe mode" option on the power-on.
If you need to restore the previous Windows 8.1 startup mode, you can enter "Bcdedit/set {default} bootmenupolicy standard" at the command prompt and return.