You did not list what OS has the issue so I am going to assume OSX 10.8 or higher. And you don't list what the CUPS soiution was. Which could be anything from adding the printer to the OS manually, to actually setting the XSA account info or enabling the prompts.
Check the last few pages of the attached pdf and go into CUPS, enable XSA account prompts, reboot and try a print.
Second, if step one fails, reset the Mac Print system, install the latest driver and follow the CUPS part of the attached pdf, reboot and print.
Third, come back to the forum and tell us if it worked, or what the the actual OS is with the issue, what is happening and what you expect to happen instead.
Be clear, and screenshots are massively helpful. To capture a defined area of your Macs screen use "Command+Shift+4" and drag your mouse to highlight the area you want captured.
I cannot get a few of the Macs In my building to print to a 5765 that everyone in the building does their mass printing to. It has been difficult for me to figure out the problem because it seems random. The two that I am having a problem with right now have two different versions of OS on them and we have plenty of computers running the same two OS on them that are printing just fine. I have called Xerox already and they gave me the CUPS solution but it is not working. It is also worth noting that these two computes are having other problems with different printers in the building. I will also point out that I am a student assistant that was hired to help the IT guy that no longer works here so normal (simple) explanations may be required. I know quite a bit but I have not been able to fix this particular issue.