'YES' button on UAC prompt is absent.

1. In the search bar type: Recovery and enter options
2. Go to Advanced startup and click Restart now
3. Click Troubleshooting.
4. Advanced Options > Startup Settings > Restart;
5. After the computer restarts, you will see a list of options. Select to enter Safe Mode with Networking.
6. On the Desktop, click the Ctrl + Shift +Esc keys
7. Click File and select the Create new task option and type: CMD check the Create this task with administrator privileges box
8. With the Command Prompt open, execute the command below and enter:

net user administrator /active:yes

After the process, Restart the computer, login as the Administrator user, and perform the steps to create a new user, access the link and create a user

https://support.microsoft.com/en-us/windows/cre...

I'm waiting for news.

I know what you mean as I upgraded from Windows 7 to Windows 10 when the free upgrade was offered. I had a user account in Windows 7 that transferred over to Windows 10. (but I did have a password) After using Windows 10 for a while I switched to using a Microsoft account but when I have clean installed Windows 10 I always use a local windows account first.

I think your local account is somehow corrupt.

The built-in Administrator account in Windows 10 is there as an emergency, but you need to make it visible. I suspect you cannot do this in the current situation as it requires a command using either a Command Prompt (Admin) or PowerShell (Admin).

Do you have a Windows 10 bootable USB (for windows installation) or a bootable DVD for the same purpose. If not you can create one yourself but you may need another PC/Laptop to create it.

The current version of Windows 10 available from Microsoft via the Media Creation Tool will create a bootable USB or a downloadable ISO (which you can use to create a boot DVD) http://www.microsoft.com/en-us/software-download/windows10

Instructions are on the website about using the tool to create the bootable media. Select Download tool now.

If you can create the media and boot from it then select Language > Repair and you should be able to access the Troubleshoot menu where you can select Command Prompt. At the prompt enter net user administrator /active:yes press return. Restart the PC to see if you have the option to use the built-in account, it should appear on the sign-in screen, there is no password.

I would suggest going to Settings > Accounts and changing your current local account to a user type account then restart using Start > Power > Restart.

Sign-in again and and using the Administrator account go back the Settings > Accounts and change your local account back to an administrator type account.

Restart again and and this time sign-in to your local account and try something that brings up the UAC again, perhaps just Command Prompt (Admin) or PowerShell (Admin).

Failing that you may have to create a new local account and start to use that instead of your previous account from Windows 7 as an administrator.

https://support.microsoft.com/en-us/windows/create-a-local-user-or-administrator-account-in-windows-10-20de74e0-ac7f-3502-a866-32915af2a34d

When you have finished using the built-in Administrator account then turn it off again by going to a command prompt, as before and enter net user administrator /active:no press return, you should not leave this account enabled.

Are you using an account created by yourself as your work a day account or the built-in Administrator account. When you sign-in to Windows 10 does the account have a name or Microsoft account?

I've read on these forums previously that using the built-in Administrator account can have this problem.

Ho ho Ju! As soon as I select Power Shell (Admin) I get the UAC Prompt without the yes button!!!

Hey,AdrianCooke

How are you? My name is Juliana and I am happy to help you today

We will scan the system and see if the error still persists.

1. Click Windows Keys + X Select PowerShell as Admin
2. Run the commands below and enter every line

sfc /scannow

Repair-WindowsImage -Online -RestoreHealth

Wait for the processes to finish, restart the computer and run the tests.

I await news, I hope I have helped!