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Can't download any extensions

  • 7 replies
  • 1 has this problem
  • 2 views
  • Last reply by tbird60

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I'm running Win7 ultimate with FF 57.0.3 and MSE with ZoneAlarm firewall. When trying to download Adblock Plus (or any other add-ons) I get "There was an error downloading ... etc. Try again." I've tried all the procedures here on this link - ' https://support.mozilla.org/en-US/kb/unable-install-add-ons-extensions-or-themes', also set up a new profile and opened from it. Cleared the cache. Uninstalled Firefox with Revo Uninstaller running a deep scan for leftover components, Reloaded FF Turned off MSE and replaced Zonealarm with Windows Firewall. Getting a little crazy, I tried running Firefox in Safe Mode (even though I didn't have any extensions loaded). Ran a Malwarebytes scan and found Montiera adware PUP that I squashed. Went to AdBlock Plus.org and clicked the download link and got.

Secure Connection Failed

An error occurred during a connection to addons.cdn.mozilla.net. The server uses key pinning (HPKP) but no trusted certificate chain could be constructed that matches the pinset. Key pinning violations cannot be overridden. Error code: MOZILLA_PKIX_ERROR_KEY_PINNING_FAILURE

   The page you are trying to view cannot be shown because the authenticity of the received data could not be verified.
   Please contact the website owners to inform them of this problem.

Any ideas??

I'm running Win7 ultimate with FF 57.0.3 and MSE with ZoneAlarm firewall. When trying to download Adblock Plus (or any other add-ons) I get "There was an error downloading ... etc. Try again." I've tried all the procedures here on this link - ' https://support.mozilla.org/en-US/kb/unable-install-add-ons-extensions-or-themes', also set up a new profile and opened from it. Cleared the cache. Uninstalled Firefox with Revo Uninstaller running a deep scan for leftover components, Reloaded FF Turned off MSE and replaced Zonealarm with Windows Firewall. Getting a little crazy, I tried running Firefox in Safe Mode (even though I didn't have any extensions loaded). Ran a Malwarebytes scan and found Montiera adware PUP that I squashed. Went to AdBlock Plus.org and clicked the download link and got. Secure Connection Failed An error occurred during a connection to addons.cdn.mozilla.net. The server uses key pinning (HPKP) but no trusted certificate chain could be constructed that matches the pinset. Key pinning violations cannot be overridden. Error code: MOZILLA_PKIX_ERROR_KEY_PINNING_FAILURE The page you are trying to view cannot be shown because the authenticity of the received data could not be verified. Please contact the website owners to inform them of this problem. Any ideas??

All Replies (7)

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Should not run a uninstaller Revo Uninstaller to uninstall Firefox.

Try connection with out Firewall and A/V as some A/V|Firewalls programs are substituting their own Certificate during the handshake which then terminates with errors. Update them and then check their Forums for any information on issues reported.

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Thanks for the quick replies guys, but as I mentioned above, I'm currently running without any antivirus protection and have already swapped out Firewall apps already too. It's not either of those.

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There is an issue going around involving the Add-ons download server getting blocked and unblocked and blocked again by Norton ConnectSafe DNS service. This may be a service that you use through your router or internet service provider even if you do not have Norton security software on your computer.

Unable to download/install ANY/ALL add-ons?

I don't current know of a workaround that wouldn't involve bypassing your regular DNS service.

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One other thing I forgot to mention - I have three other computers on the same router that are running the same OS and firewall and I'm not having any problem with them. Somehow, there's somthing wonky with this computer's setup that I'm missing...

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Hi Fred - That's the procedure I tried initially, but just for the heck of it I tried it again just now - again it didn't help. I tried not making the new profile the default and instead launched it in a new browser, then I set it as the new default, restarted Firefox and tried to download again. No go.