The reason why the operating system can't load is that the digital signature can't be verified. This operation is generally caused by installing anti-virus software such as 360 in win 10 system.

The problems encountered are shown below.

This situation is generally caused by anti-virus software.

Solution: Delete Windows/System32/drivers/ql446949.sys (if the file is different in different situations, delete whatever you are prompted).

After F8, when you enter the safe mode, you can't turn on the computer.

How to delete

Use U disk as system disk and enter PE environment.

Then delete it and look at the file above.

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