The Canon drivers from Apple are here - http://support.apple.com/kb/DL899.
See if your model is supported here - http://support.apple.com/kb/HT3669#canon.
I don't see an IR2020 anywhere on the list, though. It's possible that your printer is no longer supported.
Canon U.S.A. : Support & Drivers : imageRUNNER 2020
10x a lot guys. never thoght to look in the us site, cous i am from EU!
Thank you very much!
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