When pages come out of the copier the image is printed crooked. The paper comes out straight, so feed is correct. Image is just crooked? Why?

Most likely to be a page feed problem, look online to clean page feeder rubber rollers.
Try here for the pdf manual which covers problem with jams and skewing
http://www.hp.com/ctg/Manual/c00264334.pdf

I'm not sure what lopsided means??? Are you saying that the image is crooked? If you feed the paper 180 degree then the way you are feeding it now, are they still crooked? Also, do the pages get jammed? Also, look to see if one of the hings are broken? If one is broken, it's a dead give away for your problem. If that is not the problem, I would loosing up the screw that hold the adf on and move the adf a bit till the copies come out straight. Once the copies are coming out straight, tighting the adf hing screws and you are done...... Good Luck

Try using HP Support

HP Photosmart C6280 All in One Printer

You need to try a thicker paper, Heavier stock to double print the page. Slightly more expensive. Recycled paper typically will not work for this type of function. I had this same problem and found this was the only solution.

Push the copy button with the cover up and no paper on the glass. Is the light bar straight up and down, or is it crooked? I can't imagine how paper could go thru the machine crooked, but check it out if you can. If the paper is too thin, it may not be getting grabbed by the rollers right.

if paper comes out straight, and lines in paper are not straight then there is problem wit laser unit, its not installed corrrectly, also you can check drum unit and transfer belt for correct installation.

any stripes are usually caused by imagining unit, first use the tool in front cover to clean laser glasses. inspect IU drums for stripes maybe youll need to change them. is the page coming out ok, but picture is printed crookedly ?

I would have to say that there must be a same piece of paper touching the paper as it is being feed through the duplex ass'y. The best thing to do is to see if the copy gets tilted toward the front or rear of the copy/ copier. You will be able to find where the obstruction is in the dupex path.

dear sir please check the upper heat roller claws set,may be one of them is bended up

Ensure the guide for the plain paper onto which the image is printed, are pushed up fully. It is possible that the paper is being fed into the paper feed path at an angle if the guides are nut pushed up.