Paper cassette problem Epson Artisan 800

[curiouspalate]

My printer has been working fine for 4 months. Suddenly I got a message about the paper cassette not seating corectly. I've powered on/off and played around but can not print. I suspect the cassette detection switch (is there one?) has failed. I pushed it a few times and even tried launching a print w/the metal switch depressed but always the same problem. Any suggestions?
Thanks,
elliot