According to Canon, the supported media types are: Cards , Envelopes , Photo paper , Plain paper , Transparencies
Double check to make sure you have the current driver version.
1.10a (Windows Vista/XP/2K 32bit)
5.8.3 (Mac OS X all) Printer
Available here:
http://www.usa.canon.com/consumer/controll...wnloadDetailAct
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