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I cant download the latest version

I can not download the update version, it shown HPKP error or Key Pinning Failure. Below this i copy paste the error msg.

Secure Connection Failed

An error occurred during a connection to download.mozilla.org. 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.

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Report errors like this to help Mozilla identify and block malicious sites

I can not download the update version, it shown HPKP error or Key Pinning Failure. Below this i copy paste the error msg. Secure Connection Failed An error occurred during a connection to download.mozilla.org. 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. Learn more… Report errors like this to help Mozilla identify and block malicious sites

All Replies (1)

Could you try clearing Firefox's cache to see whether that helps?

See: How to clear the Firefox cache

If you have a large hard drive, this might take a few minutes.


If the error persists, you can remove one of Firefox's settings files that stores information about individual sites' secure connection requirements to see whether that helps.

Open your current Firefox settings (AKA Firefox profile) folder using either

  • "3-bar" menu button > "?" button > Troubleshooting Information
  • (menu bar) Help > Troubleshooting Information
  • type or paste about:support in the address bar and press Enter

In the first table on the page, click the "Open Folder" button. This should launch a new window listing various files and folders in Windows Explorer.

Leaving that window open, switch back to Firefox and Exit, either:

  • "3-bar" menu button > "power" button
  • (menu bar) File > Exit

Pause while Firefox finishes its cleanup, then rename SiteSecurityServiceState.txt to something like SiteSecurityServiceStateOLD.txt, or you can delete it.

Start Firefox back up again. Can you access that site normally again?