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Firefox won't open FaceBook on my Mac.

  • 1 reply
  • 3 have this problem
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  • Last reply by guigs

DrewPri
DrewPri
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This is the message I get (which usually offers to add a security exception, but not in this case) when I try to open FaceBook in Firefox.

www.facebook.com uses an invalid security certificate. The certificate is not trusted because the issuer certificate is unknown. (Error code: sec_error_unknown_issuer)

Also, GUI's aren't present, just hyperlinks using Firefox to browse Firefox's help page.

This is the message I get (which usually offers to add a security exception, but not in this case) when I try to open FaceBook in Firefox. www.facebook.com uses an invalid security certificate. The certificate is not trusted because the issuer certificate is unknown. (Error code: sec_error_unknown_issuer) Also, GUI's aren't present, just hyperlinks using Firefox to browse Firefox's help page.

All Replies (1)

guigs
guigs
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HI DrewPri, In your browser open up about:permissions in a new tab. Search for facebook and click "Forget this site". This will remove all the cached pages, cookies and certs for facebook locally. Restarting Firefox and logging in will request a new certificate.