Azure Backup Agent quiet mode (/q) installation doesn't work on Windows Server 2008 R2 SP1

Azure Backup Agent quiet mode (/q) installation doesn't work on a Windows Server 2008 R2 SP1 VM installed from Azure Gallery.

When I issue the MARSAgentInstaller.exe /q command, simply nothing happens. However, if I issue just MARSAgentInstaller.exe, then interactive install correct.

For a big client project, we really need quiet mode installation.

Please notice that we already acknowledged  https://support.microsoft.com/en-us/kb/2934202 .

PLEASE HELP!

Thanks,

Antonio