Living Room Rocker
Hi Martin,
 
If you would like to make this message disappear, all you have to do is open Edit>Preferences (or just press "P")>File>Initialization File (make sure you have the Advanced radio button active at the bottom left of the Preferences box) and in the Option box type "WarnSilentBuses" with no spaces.  Now add "0" (zero) in the Value field, click on the Apply button and then OK.  The next time you open SONAR or a SONAR project, you will not see that dialog box again.
 
Kind regards,
 
Living Room Rocker