1. System files are lost, and automatic repair is performed after restarting. The system file structure is disordered during repair, resulting in failure to start or take a long time; this problem is best to reinstall the system

1. The hard disk has bad sectors, this possibility is very high, because if the system file is lost, it is unlikely to be able to start successfully occasionally; it is recommended that the landlord scan the hard disk with special software or find someone who understands it