Thanks Paul & Jim for the suggestions.
One other thought - perhaps the printer is part of the problem? I used a
Xerox Phaser 8560 MFP to print them in color. It is a high quality
multi-function printer so I think that should be usable, but maybe the bar
code reader doesn't like the ink? Just guessing. I guess I'm still stumped
as to why two labels worked just fine but none of the others.