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i can't open my facebook app in this PC, how can i permit to open this app

  • 3 replies
  • 2 have this problem
  • 21 views
  • Last reply by cor-el

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i can not open my facebook account, it says that 'insecure connection" The owner of www.facebook.com has configured their website improperly. To protect your information from being stolen, Firefox has not connected to this website.

This site uses HTTP Strict Transport Security (HSTS) to specify that Firefox may only connect to it securely. As a result, it is not possible to add an exception for this certificate.

i can not open my facebook account, it says that 'insecure connection" The owner of www.facebook.com has configured their website improperly. To protect your information from being stolen, Firefox has not connected to this website. This site uses HTTP Strict Transport Security (HSTS) to specify that Firefox may only connect to it securely. As a result, it is not possible to add an exception for this certificate.

All Replies (3)

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I don't have account but I can get to their page without problem. I think it boils down to over active A/V or firewall. Otherwise if you have adblockers that could also be causing the connection issue.

Modified by WestEnd

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Hi try : uninstall Firefox. Then Delete the Mozilla Firefox Folders in C:\Program Files , C:\Program Files(x86) & C:\ProgramData Then restart system. Then run Windows Disk Cleanup. (Note: This should be Pinned and run Weekly, If never done below expect 10's of gig's) Then run it again and click the button that says Cleanup System Files. Note: your Firefox Profile is saved. But you should make a back up before you do :

Reinstall with Current Release Firefox 59.0.1 with a Full Version Installer

Please let us know if this solved your issue or if need further assistance.

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Could you please provide more detail about the issuer of the certificate?

  • click the "Advanced" button show more detail
  • click the blue SEC_ERROR_UNKNOWN_ISSUER message to show the certificate chain
  • click "Copy text to clipboard" and paste the base64 certificate chain text in a reply

If clicking the SEC_ERROR_UNKNOWN_ISSUER text doesn't provide the certificate chain then try these steps to inspect the certificate.

  • open the Server tab in the Certificate Manager
    • Options/Preferences -> Privacy & Security -> Certificates: View Certificates -> Servers: "Add Exception"
  • paste the URL of the website (https://xxx.xxx) in it's location field.

Let Firefox retrieve the certificate -> "Get Certificate"

  • click the "View" button and inspect the certificate

You can see detail like the issuer of the certificate and intermediate certificates in the Details tab.