0x610000f6 Error on HP Officejet 6500A Plus

Bit of a boring one this - but maybe useful to anyone suffering the annoyance of their HP Officejet 6500A multi-function printer playing up and complaining about the wrong paper size being in the printer.

I've had this printer since December, and it's been pretty good.  It's wireless, which is handy, my iPad prints to it and it's ink tanks are a good deal cheaper than the 350XL and 351XL cartridges I've been using until now.

However, yesterday, for no apparent reason, it stopped printing.  No matter what application I printed from (Word, Photoshop, Firefox, Adobe Reader) or even if I asked the printer to print a report or test page from it's own menus, I would get an error saying that the paper size was too small and that the printer was cancelling the job.  Annoying.

Having hunted around the internet for (what seems like) hours today, I finally found a comment which suggested a printhead alignment would do the job, and it did.

So, if you've got a HP Officejet 6500A and it won't print or complains that the paper size is wrong (when it's not) or you get a '0x610000f6' error on-screen, go into Setup > Tools > Align Printhead.

I'm sure it won't solve it everytime, but it worked for me.  I hope this post prevents someone else from wasting their afternoon.