Firt of all, make sure you are running the latest version of Windows 10. Seriously.
Could you confirm if this also happens in the default Administrator account?
Open Start
Type: cmd
Right click CMD
Click Run as administrator
At the command prompt, type:
net user administrator/active:yes
Hit Enter
Close command prompt, restart, then try signing into the Administrator account.
Do you have the latest cumulative updates for Windows 10 1803 installed?
Open Start > Settings > Apps > Apps & features
Scroll down to Minecraft
Select it
Click Advanced options
Click Reset
Restart
Check the Store for updates
If that does not work...
download the following utility and use it to remove Minecraft:
https://gallery.technet.microsoft.com/scriptcen...
Download and reinstall Minecraft for Windows 10 - Microsoft Store
https://www.microsoft.com/en-us/p/minecraft-for...