R2400 printer head problem

[mpj01]

Hello, After replacing a cartridge, the next time I turned the printer on the green light (on /off button) did not stay on, and both the ink and paper lights blink alternately. I have found reference to the replaced cartridge not seating properly, however the head is all the way to the right and I am unable to open the cover.
Any suggestions would be greatly appreciated
Thank you
Michael Johnston
Wabasha Minnesota