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I can't add add-ons to Firefox. Error: "Download failed. Please check your connection"

  • 3 replies
  • 1 has this problem
  • 1 view
  • Last reply by cor-el

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I installed Windows 10 in my PC yesterday and, since then, I can't install any add-ons on Firefox. When I try to add to firefox, it shows "Download failed. Please check your connection". I tried to use the "Save link as...", but it show that got an unknown error. I tried to changing the about:config as I saw on forums but it didn't worked. Things that may be important: Firefox version - 67.0.4 (64-bit). Allow Firefox to install and run studies is marked.

I installed Windows 10 in my PC yesterday and, since then, I can't install any add-ons on Firefox. When I try to add to firefox, it shows "Download failed. Please check your connection". I tried to use the "Save link as...", but it show that got an unknown error. I tried to changing the about:config as I saw on forums but it didn't worked. Things that may be important: Firefox version - 67.0.4 (64-bit). Allow Firefox to install and run studies is marked.

All Replies (3)

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Can you download an extension and save the file to the desktop via the right-click context menu (Save Link As) and install the extension via the about:addons page?

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Somehow it works now.

No idea what have happened.

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Maybe there was a problem with the server that got fixed.