/v Passes parameters to MSI package.
/s Causes setup.exe to be silent.
/l Specifies the setup language.
/a Performs administrative installation.
/j Installs in advertise mode.
/x Performs setup uninstall.
/f Launches setup in repair mode.
/w Setup.exe waits for the installation to finish before exiting.
/qn A Windows Installer MSI parameter that causes everything but setup.exe to be silent. This sets the user interface level to zero.
http://kb.flexerasoftware.com/doc/Helpnet/installshield12helplib/IHelpSetup_EXECmdLine.htm - jmaclaurin 12 years ago