Currently Being ModeratedDec 26, 2012 5:52 AM (in response to siricorrine)
Have you checked the Epson and Canon web Technical Support sites for updated drivers for your units that are Mountain Lion compatible?
Currently Being ModeratedDec 26, 2012 6:09 AM (in response to siricorrine)
This page says your Canon is print only unless the manufacturers website has more?
Currently Being ModeratedDec 26, 2012 6:27 AM (in response to siricorrine)
For the Scanner, try opening Image Capture and see if the scanner is listed or try the Print & Scan system Prefs.
For the Printer, have you tried removing it from the list in Print & Scan, and then adding it back?
"Unable to use" is pretty vague. There could be many reasons you are unable to use the devices. What have you done and what specific things are preventing you from using them? Scanner software doesn't open, Error messages, Printer doesn't show up in Printer list, printer shows up but error when printing, etc.