Dear angiefrey,
Your MF620C series printer is compatible with Mac OS X 10.5.8 and up as well as Window Vista, 7, 8/8.1 and 10. Based on the information you have provided, it sounds like you are using a PowerPC processor. You would need to use an Intel processor with Mac OS X 10.5.8 (and up) in order to successfully install the Mac drivers for your printer.
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