If Windows 10 is unable to boot up and takes you to the login screen or the desktop, your first step should be to use Startup Repair. Here’s how:
1. Navigate to the Windows 10 Advanced Startup Options menu. On many laptops, hitting F11 as soon as you power on will get you to the Window 10 advance startup option. Booting off an install disk and hitting Next then Repair offers a secondary option.Once your computer has booted, select Troubleshoot and then you will need to click on advanced options. Click start up repair, windows will take from a few seconds to a few minutes to attempt to fix the problem. It may not be able to. If you don’t actually have a startup problem, it will also say it can’t fix the problem.
Method 2. Safe Mode with A recovery disk Inserted
If you cannot enter Safe mode, you need to create a Windows 10 USB recovery drive. The recovery drive contains the Windows 10 recovery environment—which used to be accessible by tapping F8 on boot. Unfortunately, Microsoft decided to eliminate this feature. Creating a recovery drive requires that you have another Windows 10 computer and a USB drive with at least 512MB of storage. If you want to create a system backup (you’ll see an option to back up system files to the recovery drive), you’ll need 16GB of storage.
Launch Control Panel > Create a recovery drive. Then follow the guided instructions. After enabling USB drives as bootable drive, insert the drive into your computer and restart (this may require hitting the reset button or holding the power button down for a few seconds) and your windows will be up and running in just a moment.