Had that about 2 mo ago. Other poster is correct, your waste ink pads are saturated. The printer will run for a while but will eventually give you an error message (and ultimately quit). Unbelievably, these pads are not a user-replaceable item (very long story short). You can get it done by an Epson service center, of which there aren't many---nearest to me is about 90 mi away in Baltimore. There are workarounds which involve breaking into the printer, drilling holes and running tubing to an external waste collection bottle, reprogramming some settings. I seem to have deleted the links explaining this because it looked like an utterly amazing PITA that was also reasonably easy to screw up. I put the 2400 in the garage and ordered a new printer. If you have no money and tons of time and good mechanical skills...you may end up with a working worn-out printer. Sorry to sound negative but I'm still annoyed that Epson didn't make this an easy fix.
If I find the how-to links, I will send.