Thank you for the suggestion.
I have tried all of the suggested HP solutions you posted. There is no paper jam any where that I can find or see.
i really need to be able to take the cover off and look under where the carriage is parked to be sure there is nothing under there. But there is a plastic cover over that area. Any advice you can give on how to release the top of the printer ? The ADF and top part of the printer that is opened to access the printer cartridges is restricted from opening completely by this arm. I need to release this so that the top can be opened all the way. That will allow me to access two screws that hold the cover (the plastic cover over the area where the carriage is parked.) in place.