By older Mac OS X programs I gather you mean that your printer worked fine when running on a PPC driven Mac running OS X and now, doesn't.
Your problem is that the printer driver that you are trying to use is not designed for the Intel Mac.
I took a look at the Epson site and found a driver specifically for OS 10.4.x (Intel Mac). Have you been there and downloaded it? www.Epson.com and got to the Drivers and Support section (top Right of page)
Work your way through the system until you get to the drivers page. You need the Intel Mac driver.
This actual link is a little long to put here. The driver is for the CX 4200 series.
Give it a try
P
does anybody know how to run older mac os x programs on intel based mac operating system? I have this epson cx4220 printer that won't even read on my usb port. is this a glitch in the operating system? or is it suppose to do that? help me

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