On Windows Desktop Sharing API, UAC prompt becomes black pause screen

Question

I want to make remote assistance like application, using Windows Desktop Sharing API.

MSDN Blog says ,

What is the behavior when "Secure Desktop" pops up while sharing?
"Pause screen- Black screen with two bars(indicating pause) at lower right" is remoted when secure desktop (UAC prompts) is up on sharer's machine, when sharing process is run as a non-system process.

Yes, that is my problem. How to avoid black pause screen?
I read UAC Group Policy Settings and Registry Key Settings , and it seems the answer.
I have tried
* Set the Group policy "User Account Control: Allow UIAccess applications to prompt for elevation without using the secure desktop" -> ENABLED on both machines.
* Set Visual Studio's property "/uiAccess='true'" for the application.
* Make my own root certificate using "makecert", and install it. Also, make chained certificate for the application, and install it.
* Sign to the application using "signtool".
* Put the application under "Program Files" sub direcroty.

But still I see a black pause screen...

ADDITION
The MS Remote Assistance has a checkbox "Allow HELPER respond to User Account Control prompts", and it avoids black pause screen.
But I cannot find corresponding API or settings. Does anyone know about this?

Answer 1

Reason: UAC is run in a different, privileged session (think of it as another user just logged in) which is not accessible from any screen-sharing program of the current user.

Solution: Disable UAC. There is no other way.