Contact Epson and ask them -- they have had a LOT of problems with their drivers on MacOS 10.9.
Of course I am in contact with Epson too.
However there first questions is: Is your printer working with Applications other than photoshop... well yes it is.
Epson is probably the world leader in fine-Art printers and Photoshop the leading application for creating content for it. We as customers should not be tasked with starting communication between two of the industries most important and largest companies.
As a customer of Adobe and Epson I keep calling both customer support departments with one pointing at the other. This is getting unacceptable.
Your answer that they had a lot of problems with MacOS X (10.9) is from a customer perspective just not good enough. In the other thread you claimed that the application is calling different versions of the API (old / new).... well: CS6 not working, CC works and CC 2014 does not... which application is calling what version?
I yesterday called Jens Kinzel of Epson Germany, he is the Key Account Manager Business Unit Professional Graphics and Photo (what long title) Germany. He promised me to send me the contact details of someone higher up the Epson Support team than the people who keep asking me: Is the printer switched on... have you got the current driver... is your OS up to date... etc...
However Epson Germany is a long way from where Epson writes its drivers, most people who own a Epson Stylus Pro 7900 or 9900 in Germany will be using a RIP, a lot of others are using the additional third party program Epson promotes here in Germany (lots of money, wine emulation, evil app with dongle). So the combination OS X + Adobe PS CC 2014 + Epson print driver is quiet rare. Do you really think I can get through to where the Epson drivers are written?
Your chances as Adobe are lot better to get someone at Epson on the line who has the power to solve this problem.
I'm having this same problem with Adobe Photoshop CC 2014, a Sharp MX-6240N printer and any size paper over 8.5x11. Yes, that's write it can't even print on legal size paper.
The weird thing is Adobe Photoshop CC worked just fine and I can print on legal or tabloid oversized paper from InDesign or Acrobat, but I do not usually work in those formats as I generally work on video motion graphics. (and use Photoshop for the design) It would be a real pain to have to convert my files everytime I need to print large format.
This is obviously a problem specific to Photoshop CC 2014 on Mavericks. Other designers in my office are also experiencing this problem. I am using OSX version 10.9.4. Please fix.
Unfortuantely, Epson is the only party that can solve the problems with their drivers.
And Epson is having trouble with several applications on MacOS 10.9. InDesign and Acrobat use older print APIs than Photoshop or Lightroom, and may not hit the same bugs in the driver.
Just had to have my iMac wiped and OS X Yosemite 10.10.1 re installed as well as CS6 Photoshop and InDesign downloaded and re installed. Due to a Malware infestation! I am having the same problems with printing from PS and ID to an Epson 7900. Won't print but churns out metres of paper and cuts it up despite best efforts to stop it by turning off the auto cut? Epson not able to resolve so far after a day of online chat sessions! NOT HAPPY.
Downloaded and installed latest driver for Epson 7900 today but has NOT resolved my problem printing from iMac 10.10.1 with Photoshop CS6. Seems to be receiving some communication from computer to printer but after a few minor print head moves it just chucks out paper and prints nothing! Epson chat not able to resolve and asking me to send screen shots of print settings to an email address email@example.com ? As yet not resolved. Very frustrated and angry at this latest issue.