Open Local Group Policy Editor
Windows + R
Type Gpedit.msc
Go to the following Policy
=>Computer Configuration
=>Windows Settings.
=>Security Settings.
=>Local Policies.
=>Security Options.
Click on: User Account Control:Admin Approval Mode for the Built-in- Administrator account.
Enable the Policy
reboot/logoff
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https://feelsecured.wordpress.com/2013/12/07/how-to-solve-error-this-app-cant-be-activated-by-the-built-in-administrator-in-windows-8-1/