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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
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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 10 Contributor
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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
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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.