ITunes 8 does not automatically advance to next track in album or playlist

Question

iTunes 8 was recently installed for me by the company on my company laptop. This was done automatically by LANDesk. (We call this being LANDesked. I was forced by LANDesk to reboot my computer twice yesterday, but I digress.)
iTunes does not automatically advance to the next track in an album or playlist, either in list view or grid view.
List View: I can play any song in an album by double-clicking it or by selecting the track and pressing the play button. When it gets to the end of that track, it does not automatically advance to playing the next track. Pressing Ctrl-Right stops the current track and does not play the next track. The Next button is active and it, too, stops the current track and does not play the next track.
Grid View: Play Album button appears to be active but does nothing.
Is there some setting I'm missing that was set to do this in iTunes 7 but not in 8?

Answer 1

Thanks. That fixes the problem. I'm an idiot.
I thought the check boxes were for selecting which tracks get synced to my iPod or iPhone. I must have unchecked them all (before the installation of iTunes 8) when I was trying to figure out how to sync a 2nd computer (this one) to my iPhone.
I can't find anything in the iTunes help about this necessary fact for playing your albums and playlists. If you look on the Index tab of the help, neither check nor uncheck are found in the list. If you search for check, you eventually find, amongst all the pages, that you need to have tracks checked in order to burn them to a CD and to import them from a CD, but I find nothing about checking to play tracks. Also, the help is very confusing on the difference between selecting one or more songs and checking the check boxes of one or more song. These seem to be used interchangeably occasionally.