unable to install firefox add on

I only get a failure message: "Add on couldn´t get downloaded because of an connection failure"
what´s my problem?

1Password Version: Not Provided
Extension Version: Not Provided
OS Version: Not Provided
Sync Type: Not Provided
Referrer: forum-search:unable to install firefox ad on


  • Drew_AGDrew_AG 1Password Alumni

    Hi @LA73,

    I'm sorry you're having difficulty installing the extension in Firefox! What exact version of Firefox are you using? The latest stable release is currently 43.0. You can check for updates by going to the menu for Firefox > About Firefox. If an update is available, please install it. Does that make any difference?

    If it's still a problem with the latest version of Firefox, we'll need to know some more details:

    • What version of Mac OS X are you running?
    • What version of the 1Password app is installed on your Mac?
    • Are you using the AgileBits Store version or the Mac App Store version of 1Password?
    • What exact version of Firefox is installed?


  • HI @Drew_AG,
    im using OS X 10.11.2,
    1Password 5.4 (540046) Mac App Store version
    and Firefox 43.0.

  • all up to date and always the same message

  • Drew_AGDrew_AG 1Password Alumni

    Thanks @LA73!

    Do you happen to use any firewall or anti-virus software on your Mac? If so, it might be blocking the extension from being downloaded in Firefox. You can try temporarily disabling that to see if it allows you to install the 1Password extension.

    Alternately, you can try downloading the Firefox extension from a different browser and then install it in Firefox:

    • Open the following link in Safari: https://agilebits.com/onepassword/extensions
    • Click the link for Show all extensions.
    • Click the Install button for Firefox in order to download the extension.
    • Find the downloaded extension in your Downloads folder and drag it into a Firefox window.
    • Firefox should ask if you want to install the extension - click Install.

    If you have trouble dragging the extension into a Firefox window, you can double-click the .xpi file that you downloaded. It should give you the option to Choose Application, and when you click that, a dialog will open so you can pick Firefox (if Firefox is grayed out, change the "Enable" popup menu to All Applications, and then you'll be able to choose Firefox).

    Does that help? Let us know how it goes, thanks!

  • Thanks @Drew_AG!!!

    Perfect instruction!!!

    The add on works now.

    Thanks a lot

  • brentybrenty

    Team Member

    Excellent! Thanks for the update. On behalf of Drew, you are most welcome! I'm glad to hear that helped. However, I'd be more concerned about the root cause.

    Your 'security' software may be breaking the secure connection by installing their own certificate, which poses as the various websites you visit. Which are you using? We can't stop them from doing that; only you can. Unfortunately this is a common practice these days. You may need to remove their certificate — and you'll probably want to. I hope this helps.

  • @brenty, i´m using little snitch, but i couldn´t find anything in it to remove about firefox

  • Also i´m using Avast Mac Security 2015, but nothing in there to remove about agilebits or 1password or firefox.
    There is also no certificate at firefox to find about agilebits or 1password

  • Drew_AGDrew_AG 1Password Alumni

    Hi @LA73,

    If things are working fine with the 1Password extension, and if you don't have trouble installing other extensions in Firefox, you probably don't need to worry about this. However, it's possible you'll run into some problems if Little Snitch or Avast blocks the communication between 1Password and the extension, or if they cause a problem for other extensions.

    We have some information that might help in this knowledgebase article.

    Again, you don't necessarily need to do anything if you aren't running into any problems. But if you have more questions about that, please let us know!

  • I encountered this error, too. I notice that there are many posts in this forum concerning this error, going back at least to 2011. My solution may be of interest.

    I run the Thunderbird (TB) email program. TB uses parts of Firefox (FF), so it keeps them open. When I close both TB and FF, I am able to install the 1Password addon to FF. During installation, 1Password (1P) starts FF and installs the 1P addon. Then I can restart TB myself.

    Of course, this solution still does not help those who do not use Thunderbird. Those people might be running some other program that keeps parts of FF running, or there may be some bug in 1P. Note: it should be possible to track down this problem by running a process monitor or process explorer, such as Procmon.exe from Sysinternals. Procmon can show you what FF files are running, and you can use Procmon to track down which other program is running them. Best of luck to all.

  • Drew_AGDrew_AG 1Password Alumni

    Thank you for sharing your solution, @DavidSpector! :) It sounds like that might be really helpful for someone in the same situation.

    I've noticed that error message is often the cause of something else blocking extensions from being downloaded in Firefox. We've seen this happen a lot with Avast, although other software can cause the same thing. I'm not sure if that's the case on your computer, or how that fits in with your findings, but thought I'd mention it.

    Again, thanks for taking the time to let us know about what worked for you on your computer! If you need anything else, be sure to let us know. :)

  • Interference from an antivirus or anti-malware program is a completely different issue. No one would ever use Avast if they did a little research first. Deliberate blocking of adding an addon is different from your installation program requiring that Firefox be completely closed, including any applications that keep Firefox open. You have many open and unanswered posts on this forum that could now be answered more helpfully.

  • @DavidSpector I, too, use Firefox (FF 45, in fact) and I also use Postbox, which is based on Thunderbird. I have no need to close either program in order to install the FF 1P extension. I mention it only to provide an alternative perspective on your own theory.


  • brentybrenty

    Team Member

    Interference from an antivirus or anti-malware program is a completely different issue. No one would ever use Avast if they did a little research first. Deliberate blocking of adding an addon is different from your installation program requiring that Firefox be completely closed, including any applications that keep Firefox open.

    @DavidSpector: Just to clarify, we don't have an "installation program requiring that Firefox be completely closed". The 1Password extension is not actually part of 1Password. Like all browser extensions, it's a separate piece of software that conforms to the browser's specifications. And 1Password cannot install it in the browser either. This is why you have to either go to the website using Firefox and install it directly, or download the file manually and drag it to Firefox: Firefox itself handles the installation of browser extensions, but unfortunately if other apps interfere with the connection itself or the browser's security settings it can cause a lot of headaches. :(

This discussion has been closed.