Epson Stylus Color 850 print gibberish

Our epson Stylus Color 850 will only print out gibberish, it looks like all different fonts and commas. Even when trying to print one word it will print out pages and pages of gibberish until the paper runs out. Initially iy happened only once in a while but now it will not print anything else.Our computer is a hp pavilion 522a Do you have any advice on what we can try to do..many thanks