iMovie: Fast User Switching and DV Camera Control
If Fast User Switching in Mac OS X 10.3 is enabled, make sure other users have logged out of their account if you can't use a camera connected to the computer.
This article has been archived and is no longer updated by Apple.
If you can't control a DV camera connected to the computer, or if iMovie doesn't recognize it, other users may be logged in and accessing the camera in iChat, iMovie, or another video application. Make sure other users have logged out of their accounts.
Note: Switching users while importing footage may cause the import to stop.
Published Date: Oct 7, 2016