Step-1

1. Go to the Desktop. Press the WinKey + R to display the Run dialog.

2. Type gpedit.msc and click OK. This will open the Group Policy Editor.

3. Navigate to the following location.

Computer Configuration/Windows Settings/Security Settings/Local Policies/Security Options.

4. On the right side, scroll down to the following policy.

User Account Control: Admin Approval Mode for the built-in Administrator account

5. Double click this policy to open. Select the Enabled option and click Apply/OK.

Step-2

Now press windows key and R and type  regedit

press enter and go to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\UIPI

And on the right hand side double click on default and change the value to “0×00000001(1)” and click ok

Restart your computer and all the apps should work.

This methods works for me in Windows 8.1 x64 with Built-in Administrator account.

Does it work for you guys?