published apps

Hello, One of our users is unable to run any published applications. Their connection settings look correct. The first time they tried, they received the following error message. "[516] Client could not access the remote application. The machine might be too busy to accept new connections or...

We have an Azure VM running Parallels RAS. Our only access is remote users accessing published apps via the Parallels RAS and the occasional Admin logging on the VM via RDP for maintenance. In this scenario it seems to me I do not need the Azure 'Front End' VPN as the Parallels is providing...