I have been trying to uninstall my Epson Workforce 500 printer. When I think I have done that, I get a message "can't uninstall Driver". I googled instructions on how to uninstall the printer and followed them to the letter, but cannot get rid of the driver. Please help!

I bought ink today and installed the magenta color that was out. When I printed a test sheet, I only get part of what I am printing. It prints 2 1/2 lines and skips two and 1/2 lines. I get a sheet with lots of white spaces where there should be print. I tried it several times just in case it needed warming up or something. I really thought I was fixed up. Any suggestions?