A log file for the Setup.exe bootstrapper can be created by passing the /debuglog parameter to Setup.exe.  This will work for Basic MSI, InstallScript MSI, and Web projects.  This first example will generate a log file in the same directory as Setup.exe, provided that Setup.exe is not in a read-only location:

     setup.exe /debuglog

If you would like to specify a directory location for the log file, you can do it this way:

     setup.exe /debuglog"C:\LogFileFolder\LogFileName.log"