Thanks for reaching out! I'm an Independent Advisor and a Microsoft user like you.
Kindly try the steps below, hopefully, this may help you access your son's laptop. Kindly perform them in sequence. My apologies for the long response.
NOTE: If one of the methods below will be able to help you access your Windows desktop again, I suggest that you create a backup of all your important files.
We need to boot to Advanced Recovery Mode to check and fix errors on your system that may be causing this problem. Here are some ways on how to access the advanced recovery environment:
https://www.lifewire.com/how-to-access-advanced...
or you can try below:
a. Power on and off your computer three times.
b. On the third time, your computer will boot into the Advanced Recovery environment
c. You will know when you are in the Windows Recovery Environment if you see a blue Choose an Option screen or a blue Troubleshoot screen.
Now once you are in the Recovery Environment screen, please follow the steps:
Method 1: Enable Built-in Admin Account for Windows. May not work with Windows 10 Home, but please give it a try.
1. Click Advanced Options
2. Click Troubleshoot
3. Click Advanced Options
4. Select the Command Prompt option to troubleshoot windows.
5. In command prompt type: net user administrator /active:yes
6. Press “Enter“. Restart then you will have a basic administrative account to use with no password
Method 2: If the above steps did not work, please try the steps below on how to manually create a new admin account without Logging in
1. Go Back to the Recovery Environment screen select Command Prompt
2. When you see a Command Prompt, type the following commands and press Enter after each command.
copy d:\windows\system32\sethc.exe d:\
copy /y d:\windows\system32\cmd.exe d:\windows\system32\sethc.exe
4. Once that's finished, restart the computer
5. After you see the logon screen, press the SHIFT key five times. The Command Prompt should open and you can run the following commands to create a new admin account.
Type the following commands and press Enter after each command. Make sure to replace the value of {user_name}.
net user {user_name} /add
(Ex. net user joe /add)
net localgroup administrators {user_name} /add
(Ex. net localgroup administrators joe /add)
6. Reboot and you can then log in to your Windows computer with the new admin account.
NOTE: Once you are back to your desktop, you can also create a new admin account or grant an account administrator rights if needed.
See the article below:
https://support.microsoft.com/en-us/help/402692...
Method 3: Please watch and follow the steps carefully in this video tutorial, let's see if this would work in your favor.
https://www.youtube.com/watch?v=NW00gdvSYoU
NOTE: If one of the Windows Updates caused this issue you may try to uninstall the problematic update.
If you are able to login to the desktop, click Windows > Settings > Update & Security > Windows Updates > Update History, uninstall them there.
Restart and check. If the problem was resolved then check and block the problematic updates. See link below:
https://www.howtogeek.com/223864/how-to-uninsta...
If you find the suggestions to have worked for you, please mark it as helpful. Feedback definitely helps us all. Let's hope for the best. Stay safe.
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