WDAC Managed Installer: Company Portal

[wantab]

Hello, 

I've successfully created and pushed our WDAC policy using Intunes & OMA-URI. 

In the WDAC policy I've enabled installations through a "Managed Installer" and want to add Intunes\Company Portal as the managed installer, but I have not been able to. 

The only instructions I have found to accomplish this is this link (Windows Defender Application control - Part 2), The script offered on the page executes, but errors out (even locally with an admin/elevated powershell).

It fails with this error:

Does any know why it is failing, or have a better solution to "whitelist" Intunes/Company Portal as a Managed Installer?

Thanks, 

Brandon

[#2]

@wantab 

If you are still searching: Check out the new possibility to set the Intune Management Extension as managed installer.
Manage approved apps for Windows devices with Application Control policy and Managed Installers in M...