I don't think he is using standard account. He is using Administrator account but something broke something and he gets an error msg instead of UAC prompt.Wait then why are you using a standard account (it's limited) on windows 10? This account is only meant for kids, guests or employees.
You should login into administrator account first and then scan the disk. All computers have at least one admin account.
Over the years I have found and experienced that there are times when the simplest and best solution is to just format and start fresh. It can not be true for all as it depends on number/types of programs installed, level of customisation done on the system, and how hard is it getting to troubleshoot and fix. OP here seems to have a very limited use case (and hence I'm assuming that not many programs would have been installed) so IMO it would be best to take a backup and reinstall windows.
I used to be all in for troubleshooting but over the years amount of free time reduced and hence a lot of things changed.