Question : Problem: HP Designjet 450c Issues

I am attempting to install a designjet 450c onto a pc after the printer has be sitting for nearly a year. i have installed the drivers and its seems fine. On the printer on the error lights sections the media error light is lit. I have gone to the hp site looking for solutions but no luck. I have tried contacting hp but they no longer support this printer. Please help!!!

Answer : Problem: HP Designjet 450c Issues

It could be either the pinch arm sensor or the cover sensor. To perform a sensors test, do the following:
Perform a sensors test in service mode 1. Enter service mode 1
by turning the printer on while holding down the REPRINT key. Continue holding down REPRINT for 3 seconds after power on.
After all the front panel LEDs begin to flash, press MEDIA TYPE to enter the sensor test.
Open the top cover, the FILM LED should change status. If nothing happens, the top cover
sensor is probably bad. The cover sensor is part of the front panel assembly.

 
look here:  http://h41186.www4.hp.com/country/us/en/forums/tree_display.html?forum_id=28&pageseq=986110