Failed to install MSIX application with error 0x80072efd

Hi

I'm pretty new to the MSIX installer and facing some issues with proxy.

If I try to install my own coded MSIX installation on a company device it fails with the error code: 0x80072efd. The company device is behind a proxy. Currently, I try to find out which URLs have to be whitelisted to get the installation done. Is there a possibility to debug the msix installer to get more info out of it? I already checked the app installer logs on the Event-Viewer but it did not help at all.  Also if I try to run the App installer from PowerShell (with the Add-AppxPackage command) it fails with the same error and links to the help page "http://go.microsoft.com/fwlink/?LinkId=235160".

Important to mention: if I run the installation from a "non-company device" the installation works as expected.