When distributing a Director movie with a linked QuickTime video, it's useful to detect if the end user has the current version of the QuickTime player installed on their system. The Lingo command quicktimeversion(), available in Director 7 and later, can be used to do this.

The following frame script checks if QuickTime 3 or later is installed on the user's system. If QuickTime is installed, the movie continues to the next frame which contains the digital video. If QuickTime is not installed then the movie jumps to frame 50 which displays alternate content or, perhaps, a message telling the user they need to install the most current version of the QuickTime player.

on exitframe
 if quicktimeversion() < 3 then
  go to frame 50
 else
  go to the frame+1
 end if
end  

Note: Using this script requires an understanding of Lingo. For information about how to write scripts, see the section in the help documentation entitled 'Writing scripts with Lingo''.

Additional information
Director Online has an in-depth article on detecting QuickTime.