Cannot install add-ons (conection failure)
Recently I have been unable to install add-ons on Firefox. The add-on downloads then I get an error message telling me that the add-on couldn't be installed because of a connection failure to the site. I have tried installing different add-ons in various ways (private browsing, safe mode) but to no avail, I always get the same message. The only way for me to install an add-on is to download it first to my computer then open it with Firefox.
This is a recent problem, I installed some add-ons a couple of months ago without any trouble. I'm beginning to think that something was broken during a recent Firefox update. This is the log that I get (when I press F10) when I try to install an add-on: "Une demande multi-origines (Cross-Origin Request) a été bloquée : la politique « Same Origin » ne permet pas de consulter la ressource distante située sur ..." (A multi-origin request (Cross-Origin Request) was blocked: the "same-origin" policy does not allow access to the distant source on....) Ironically the troubleshooting window does not open for the same reason, I had to follow the manual steps.
Thank you for your help on this matter.
All Replies (6)
Hello,
Many site issues can be caused by corrupt cookies or cache. In order to try to fix these problems, the first step is to clear both cookies and the cache. Note: This will temporarily log you out of all sites you're logged in to. To clear cache and cookies do the following:
- Go to Firefox > History > Clear recent history or (if no Firefox button is shown) go to Tools > Clear recent history.
- Under "Time range to clear", select "Everything".
- Now, click the arrow next to Details to toggle the Details list active.
- From the details list, check Cache and Cookies and uncheck everything else.
- Now click the Clear now button.
Further information can be found in the Clear your cache, history and other personal information in Firefox article.
Did this fix your problems? Please report back to us!
Thank you.
I obviously did that, even used CCleaner, no luck.
Sometimes a problem with Firefox may be a result of malware installed on your computer, that you may not be aware of.
You can try these free programs to scan for malware, which work with your existing antivirus software:
- Microsoft Safety Scanner
- MalwareBytes' Anti-Malware
- TDSSKiller - AntiRootkit Utility
- Hitman Pro
- ESET Online Scanner
Microsoft Security Essentials is a good permanent antivirus for Windows 7/Vista/XP if you don't already have one.
Further information can be found in the Troubleshoot Firefox issues caused by malware article.
Did this fix your problems? Please report back to us!
Modified by user669794
There's no malware or virus on my computer, I have a permanent antivirus installed (Bitdefender). This problem with Firefox is not new, see this thread for example: https://support.mozilla.org/fr/questions/855759
Boot the computer in Windows Safe mode with network support (press F8 on the boot screen) as a test to see if that helps.
Can you at least download and save the extension XPI file to your computer?
- I can download the XPI file on my computer and then open it from the Firefox menu, the add-on is then installed.
- I tried booting in Windows Safe Mode with Network Support and I was able to install the add-on directly (so without downloading it first to my computer). So in Windows Safe Mode it works fine.
- I don't have this problem with Google Chrome, it's only with Firefox.
Any idea as to what is going wrong?