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Cannot connect to secure webpage: Error: Secure Connection Failed. Certificate contains unknown critical extension (Error code: sec_error_unknown_critical_extension)

  • 2 replies
  • 11 have this problem
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  • Last reply by quixote65

quixote65
quixote65
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Secure site connections are failing on Firefox 5 (Mac or PC), evidently due to failure to load mid-level certificates. This was evidently not an issue on Firefox 4. This problem does not exist in Safari 5 or IE.

Secure site connections are failing on Firefox 5 (Mac or PC), evidently due to failure to load mid-level certificates. This was evidently not an issue on Firefox 4. This problem does not exist in Safari 5 or IE.

All Replies (2)

eplata
eplata
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Is there a solution that solves this problem in FireFox???

Regards.

quixote65
quixote65 Question owner
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Not an automated one. Initially, I accepted the new certificates via Google Chrome. Because I happened to know the origin of the certificates in question, I was able to select and export the certificates (using .cer format) from Keychain Access, then import them into Firefox Preferences/Advanced/Encryption (tab)/View Certificates (button)/Authorities (tab)/Import... (button).

The good news is that I was able to download and import that same file to multiple workstations. The bad news is it's a manual process.