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Facebook.com and youtube.com; firefox says they don't recognize thier certificate issuer. How do I fix this?

  • 2 replies
  • 1 has this problem
  • 19 views
  • Last reply by FredMcD

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MOZILLA_PKIX_ERROR_KEY_PINNING_FAILURE

This error also appears, yesterday I didn't have this problem.

MOZILLA_PKIX_ERROR_KEY_PINNING_FAILURE This error also appears, yesterday I didn't have this problem.

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Separate Security Issue: Update your Flash Player Note: Windows users should download the active_x for Internet Explorer. and the plugin for Plugin-based browsers (like Firefox).

Note: Windows 8 and Windows 10 have built-in flash players and Adobe will cause a conflict. Install the plugin only. Not the active_x.

Flash Player Version: 24.0.0.194

https://get.adobe.com/flashplayer/ Direct link scans current system and browser Note: Other software is offered in the download. <Windows Only>

https://get.adobe.com/flashplayer/otherversions/ Step 1: Select Operating System Step 2: Select A Version (Firefox, Win IE . . . .) Note: Other software is offered in the download. <Windows Only>


See if there are updates for your graphics drivers https://support.mozilla.org/kb/upgrade-graphics-drivers-use-hardware-acceleration

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There is security software like Avast, Kaspersky, BitDefender and ESET that intercept secure connections and send their own certificate.

How to troubleshoot the error code "SEC_ERROR_UNKNOWN_ISSUER" on secure websites