When you publish a Remote desktop application trough the RDs Web Access, you goth the notification that the application that you are going to start is not authorized.
To solve this problem, you can apply the registry key on the local machine
Windows Registry Editor Version 5.00 [HKEY_LOCAL_MACHINESOFTWAREPoliciesMicrosoftWindows NTTerminal Services] "TrustedCertThumbprints"="1d 93 45 d6 0c 07 d6 a9 87 ce 78 d6 5c 3f 20 9a 6c 89 45 36" "AllowSignedFiles"=dword:00000001