Try the the info in the link below.
http://www.tenforums.com/tutorials/2304-safe-mode-start-windows-10-a.html
If that does not help then try the info below to repair 10.
If you downgraded to or have 10 you can create a install/repair thumb drive with the link below. This will allow you to boot the system and try to repair 10 first and if that does not work do a fresh install. Make sure you have a good product key and all the drivers before starting a fresh install.
https://www.microsoft.com/en-us/software-download/windows10
Once you get the thumb drive made then you can boot from it. When it boots, select your language preferences, and click next. When the next window comes up look to the bottom left hand corner and select repair my computer and then select troubleshoot.
The two link below will show you how to restore it to Last Known Good Configuration (your most recent settings that worked) and if that does not work then you can use reset it.
http://www.tenforums.com/tutorials/4588-system-restore-windows-10-a.html
http://www.tenforums.com/tutorials/4130-reset-windows-10-a.html
If none of this works then you can skip down to the bottom part about doing a fresh install of 10 if you have no files you wish to recover.
The next thing is to try to recover your files. For this you will need a bootable thumb drive(flash drive) so you can boot the lappy. This will also allow you to verify that the lappy and its hard drive is good and all you have is a Windows problems. You will need to find a working puter to download RUFUS USB installer. You need to read the instruction carefully and know a little about Linux to use this. There can be dragons present if you do not understand what your doing. I make no guarantees.
https://rufus.akeo.ie/
Once you make the bootable thumb drive you need to add a OS for it to boot. I recommend Linux Mint ISO. Its UI is similar to Windows. Download Cinnamon 32bit.
http://linuxmint.com/
If you have a Windows 8 or above then you need to turn off secure boot and select boot from USB before using the thumb drive. The thumb drive boot will also allow you to check out the rest of the puter. If it boots and everything else works then that is a good indication that the drive is bad.
If it has a CD/DVD you can burn Linux Mint ISO right to a CD and boot with it.
Once you got the bootable thumb drive created, insert it into one of the USB ports. Also plug in the medium you selected to copy your files to. Press the power button and start tapping the F key opens the boot menu. Select the USB thumb drive and it will boot to a menu asking if you want to start Linux Mint. Click on Mint and let the system boot. Find your hard drive and copy your files to your back up medium. If the hard drive is a SATA drive it will show as sda. If it has partitions then the first partition (C Drive) will show as sda1, the next partition will show as sda2 and so on. If you have 2 drives the next drive will show as sdbx. X being the partitions if it has any. Normally external drives show as sdd or sde. I have seen Linux recover data that people claimed could not be recovered. Keep in mind while looking for your files, and this is a Vista or above version of Windows, that you have to find your USER folder. The folder will look something like this. \Users\nameofuser\Documents. Repeat that for music, pictures, and videos.
Lets see if the hard drive can be made to boot again.Since the repair options are not working your best bet is to do a fresh install of 10. This will erase everything on the hard drive.
Use the bootable Windows 10 thumb drive and follow the instructions in the link below.
http://www.tenforums.com/tutorials/1950-windows-10-clean-install.html
參考: TWB 35+ years of experience in the service industry. You name it, I have probably fixed it. I have spent a life time taking things apart, seeing how they are made and fixing them. The difficult we do right away, the impossible just takes a little longer.
I'm old school. I show others respect. I will always help when needed. That is the country way.
I hear voices, so please be quiet so I can listen to them.