Use the Windows Media Creation Tool to download the Windows 10 installer and "copy" it to a bootable DVD or USB-stick. Then use that to reinstall Windows 10. Since it already was installed, there are no license issues.
My laptop was setup with a dual boot of Windows 7 and Windows 10, each in a different partition. I wanted to also install Linux as a 3rd boot option, so I created a bootable USB stick with Ubuntu on. During the Ubuntu installation process, I attempted to shrink the partition containing Windows 10 to free some space for Ubuntu. This resulted in a partition that the Ubuntu installer recognised as unusable. I think this has something to do the laptop manufacturer (HP) setting a limit on the number of partitions allowed.
Anyway, at this point gave up with the Ubuntu installation and decided to maybe try again some other time. Everything was fine for a day or two, then Windows 10 stopped booting up. Now when I boot the laptop I get "Preparing automatic repair" then "Diagnosing your PC" then "Automatic repair, your PC did not start correctly" messages.
I want try and fix the Windows 10 not booting problem then if possible complete the Linux installation as a 3rd boot option.
There are some advanced options available after the "Automatic repair, your PC did not start correctly" message ;
1.) System restore ; No restore points available so no use I think
2.) System image recovery ; No image available so no use I think
3.) Start up repair ; Just takes me back to "Preparing automatic repair" then "Diagnosing your PC" then "Automatic repair, your PC did not start correctly." messages.
4.) Use another operating system ; I can still load Windows 7 by using this option. In Windows 7 I can access the file system / drive for
Windows 10, and at a glance all the files seem to be intact / no problem.
5.) Command prompt ; This takes me to x:\windows\system32. I tried entering some commands here that I read could help ;
bootrec /fixmbr ; Said "The operation completed successfully"
bootrec /fixboot ; Said "access denied"
bootrec /rebuildbcd ; Said "Total identified windows installations: 0" then "The operation completed successfully"
I navigated to the Windows folder in the Windows 10 drive in this command wndow, and ran the same commands and got the same messages back. When I restarted the machine, I still get "Preparing automatic repair" then "Diagnosing your PC" then "Automatic repair, your PC did not start correctly." messages.
6.) Start up Settings ; Allows me to start in safe mode and some other options. All the options seem to just give me the "Preparing automatic repair" then "Diagnosing your PC" then "Automatic repair, your PC did not start correctly." messages.
7.) Go back to the previous version ; Could be the last resort. All my important files are backed up so I could try this, however I fear it may take me back to Windows 8 which is the OS that came with the laptop, this wouldn't be great because I am not sure I would be able to upgrade back to Windows 10.
Any advice would be greatly appreciated, thank you in advance.

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