Dear pokiZC!
Welcome to the Microsoft Community!
We are very sorry that you cannot log in to your computer normally. This may be related to the problem of the email of your account's primary name or the problem of network connection synchronization. Now the most important thing for us is to enter your computer and back up the data.
I think you can try a solution shared by our community users who are locked in the Windows lock screen interface. The following is the thread link:
Locked out of PC by Windows 10 - The fix is here! - Microsoft Community
You can try to back up and export the data of the user account logged in by your original Microsoft account in the newly created administrator user account in the above solution.
Final solution:
However, if you have tried the above solutions and it does not work, and your computer will always crash and blue screen, we can try to reinstall the Windows operating system to solve your system-level conflicts, because these blue screens and crashes will also affect your own use. We can remove your hard drive and connect it to another available computer to export and backup the data. The most important premise is that you do not turn on the BitLocker option, so your data will not be able to be exported and backed up normally.
After exporting the backup, you can refer to the following solution to reinstall Windows on your computer:
Disclaimer: This method will delete all your files and programs, so be sure to back them up first.
Before proceeding, please check the following:
To download and create Windows 10 installation media, use a blank USB drive with at least 8 GB of space and a working PC.
Explanation:
- Visit Microsoft Website: Download Windows 10 (microsoft.com)
- Under Windows 10 Disk Image (ISO) Download, hit Download Tool Now.
- Launch the downloaded tool and follow the on-screen instructions to create a bootable USB drive.
On the affected computer:
- Start your PC using a Windows 10 USB flash drive.
- Press any key to continue.
- Click Next.
- Click Install Now.
- Settings will also prompt you to select the Family version.
- Select the "Accept Acceptance Conditions" option.
- Click Next.
- Customize: Select to install Windows only.
- Select the option to delete all existing partitions.
- I'll complete it as described on the screen.
This process may take an hour or so. Please ensure that the power is continuously on and wait patiently for activation and driver installation. If you have any questions, please let me know at any time.
Thank you for your cooperation and understanding!
Best regards,
Yang.Z - MSFT | Microsoft Community Support Specialist