How to fix the error Downld file now SEND RFU UPGRADE

The quick fix (quick for you since you’re reading this article) for a cryptic error message for the HP Color Laserjet CP3505n printer.

So I saw this printer lying on its side at a friend’s house so I asked him what was wrong.. “Oh, I think it needs a firmware update, but no one has been able to fix it” he responded. Firmware you say?? Sounds easy-peasy to me so I told him as much with that smug smile we IT guys are so good at. He told me to take it and fix it if I could…”It’ll be another article for your blog” he said, to which I retorted “Not likely! If it’s a firmware update then it’s gonna be a one-and-done with the firmware utility…printers don’t usually lend themselves to interesting problems.” I was wrong.

Once stuck with this error, the printer goes into a loop which would make most people tear their hair out. In fact, my buddy had already bought a replacement and written the thing off for the scrap heap before I even was aware of it. But I digress.

Here is what worked for me:

1. Turn the printer on and then plug into the USB port
2. Add the printer using an HP driver such as the HP Laserjet 4100 PCL 5 (make sure you name the printer “Hewlett-PackardHP LaserJet USB Upgrade”   **note the exact string includes no space between Packard and HP**
3. Run the firmware upgrade utility and select that printer from the dropdown. It should run the upgrade no problem.

Before I hit on that combo I tried a couple other solution suggestions from partial info on various websites. If the above doesn’t work for you then feel free to try them as well. This includes:

http://www.vanguardsys.com/whmcs/knowledgebase.php?action=displayarticle&id=216
The fix in the first paragraph threw me because it sounded so good but just didn’t work for me despite multiple tries. My solution above is actually a much stripped-down version of the text that follows that first section…follow it if you want/need a step-by-step.

http://www.printerhacks.com/fixing-the-dreaded-rfu-load-errorsend-rfu-upgrade-on-cp3505-using-a-mac/
This appears to be a good solution for MAC judging by the high # of comments praising the writer. If you have a mac then you can try this and it likely will work for you (modifying it for the Vista PC I was on did not work for me at all.)