Join the AMA (Ask Me Anything) with the Firefox leadership team to celebrate Firefox 20th anniversary and discuss Firefox’s future on Mozilla Connect. Mark your calendar on Thursday, November 14, 18:00 - 20:00 UTC!

Avatar for Username

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

This thread was archived. Please ask a new question if you need help.

I'm unable to download or install any extensions within Firefox.

  • 2 replies
  • 4 have this problem
  • 1 view
  • Last reply by Veritastar

Evilsports
Evilsports
more options

When attempting to install any extension through Firefox addon's I receive a "Download failed. Please check your connection" message.

When attempting to install directly from an extensions website I receive a corrupt addon pop up box.

I've tried uninstalling my AV (Avast), changed the "xpinstall.signatures.required" from true to false.

Extensions install successfully on other browsers (Edge).

Firefox 66.0.3 64-bit Windows 10 Home Version 1809

When attempting to install any extension through Firefox addon's I receive a "Download failed. Please check your connection" message. When attempting to install directly from an extensions website I receive a corrupt addon pop up box. I've tried uninstalling my AV (Avast), changed the "xpinstall.signatures.required" from true to false. Extensions install successfully on other browsers (Edge). Firefox 66.0.3 64-bit Windows 10 Home Version 1809

All Replies (2)

jscher2000 - Support Volunteer
jscher2000 - Support Volunteer
  • Top 25 Contributor
more options

Sorry, the Add-ons team is working on a fix for this. It looks like a certificate used to sign many popular extensions expired. (The verification process checks that certificate.)

I don't know how soon re-signed versions of those extensions will become available, or whether another workaround will be discovered. We are all hoping to learn more soon.

Veritastar
Veritastar
more options

This isn't a problem on your end. This is happening to quite a few people, probably everyone I'd guess. This is only a temporary problem and they are working on fixing it. You are not alone. I'm just glad I found this forum. I was able to get answers, and now I can help other people.