I emailed HP to let them know that Firefox had disabled their software, and got the typical "I-Will-Explain-What-Has-Happened-Without-Reading-Your-Email" answer. The exchange basically went thusly:

Me: Firefox changed, and HP Web Printing doesn't work anymore, Firefox says it's the responsibility/problem of the 3rd party software vendor (HP). I am informing you of this situation, 3rd Party Software Vendor.

HP: I would be absolutely thrilled to help you! I have divined that your printer is not working because HP Web Printing is not compatible with the new version of Firefox! Email back if I have confused you in any way! Please have a wonderful remainder of your life!

Me: ...

I think anyone with this problem should email HP en masse to encourage them to come up with an extension that works. If enough of us squawk, maybe they'll actually do something. I emailed HP by clicking on the "Contact Us" link, and then clicking "Email Technical Support After You Buy".

I am having this exact problem, Firefox does not print to HP Photosmart C4100 set up as a network printer, I have also tried printing locally through Firefox to no avail. Printing through Internet Explorer works without any problems.

See this:
http://kb.mozillazine.org/Problems_printing_web_pages

The lack of compatibility of the HP Smart Web printing addon shouldn't keep an HP printer from working with Firefox - all you lose is that silly floating toolbar and a few features it adds.

File > Print or {Ctrl + P} should still initiate printing, so all you need to do is make sure the correct printer is selected and then hit the OK button.

My advice is to try the reset mentioned in that KB article.

1. Ctrl + P doesn't work. It spits out the same error message as previously mentioned:

"An unknown error occurred while printing."

2. Using the instructions at your link, I went to about:config, where I got a long warning explaining that changing stuff in there could "be harmful to the stability, security, and performance of this application" - "this application" presumably being Firefox. Awesome. After assuring Firefox that I wasn't going to break it, I proceeded to look for print.print_printer. Eventually I had to filter for it. Once I found it, I reset it according to the directions on your URL, and restarted Firefox per instructions. (It updated itself AGAIN, to 3.6.10 during this restart.) Crtl + P. Printout achieved.

Thanks!

Ballistica did not understand the question. My HP printer works. HP Smart Web Printing is a software program with other features besides simply printing. I am unable access it through Firefox. Please advise.

HP hasn't updated their Smart Web Printing application for Firefox 3.6.

Sorry, I've been through that procedure but neither the "about:config >reset", nor the" Ctrl P" work. The printer knows it is supposed to do something because it it churns out a blank sheet of paper, but that is all

We have this problem on two desktop machines running Firefox 3.6, both of which printed fine before that particular upgrade. We don't have the problem on a laptop which is on the same wireless network and which has NOT been "upgraded" ( DOWNGRADED would be more appropriate) to 3.6.

Much as I dislike HP's frequent software upgrade failures, I think it somewhat unfair to blame HP because Firefox is altered and Mozilla expects everyone else to run around after them!

I have the exact same problem. I updated to 3.6.12 and encountered the "blank page" printing problem. I ended up re installing Firefox 3.0.19. Printing works great. Also Firefox 3.5.15 gave the same blank page printing problem. I also installed "Better privacy" and " Ghostery"at the time of updates. These programs do not run under the 3.0.19 version. Not sure if if they are related to the problem. Good luck and hope a solution to the problem comes about.

I am having this problem, but I don't have an HP printer, I have a Canon Pixma MP270. I just got off the phone with the support people for Canon, and we did a bunch of tests. The printer is fine, and prints from Internet Explorer and ever other thing on my computer, but will not print from Firefox since about 2 updates ago. I get the same error message that these guys are getting. Also I keep having problems since this update with it running very slowly, not loading links properly and crashing. Sounds like there is a bug in the update that needs fixing!!!!!

I have this problem too but only with printing from secure websites. I can print successfully with Internet Explorer but not from Firefox.

I have resorted to saving the page and re-opening and printing it in Internet Explorer. Which works OK, and suggests to me that the fault lies with Firefox and not HP.

my printer used to work but I can not get it to print, it just blinks error,please fix and clean up what ever it needs.

I have the same problem but I have a Lexmark 3100 printer. I get a message: Function address OxO caused a protection fault . Exception code OxO0000005. When I go to properties in my print box. If I say OK I get: The application property sheet page may not function properly so I click OK then it crashes. I also have resorted to copying to a word doc if possible and printing it. If I use the old universal web browser it works fine. The fault is with the upgrade of Firefox.

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