Windows 7 64bit SP1
TightVNC 2.7.10 MSI installer
Command: msiexec /i tightvnc.msi /quiet /norestart SET_ALWAYSSHARED=1 VALUE_OF_ALWAYSSHARED=1
When custom parameters are combined with quiet/progress only installation mode and after installation "TightVNC Service - Control Interface" is started it says "Please Wait while Windows configure TightVNC" and after that all custom parameters that are configured by installer are overwritten with default ones. And every time when Control interface is started from Windows Start Menu, registry settings are replaced with default ones again. This behavior dose not exist with "normal" installation mode.