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support.mozilla.org uses an invalid security certificate. The certificate is not trusted because the issuer certificate is unknown.

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Hi, most of websites - google, Facebook, YouTube, ... keeps on saying that the connection is untrusted. I had an issue before, so I deleted some certificates and it seems that I cleaned too much. 1. I tried uninstalling and installing Mozilla again and nothing. 2. I renamed the file cert8.db to cert8.db.old in the Firefox Profile Folder to reset all root certificates. But it did not help. 1. My date and time is correct. 2. Save mode did not help. Anyone can help me please? Thank you

Hi, most of websites - google, Facebook, YouTube, ... keeps on saying that the connection is untrusted. I had an issue before, so I deleted some certificates and it seems that I cleaned too much. 1. I tried uninstalling and installing Mozilla again and nothing. 2. I renamed the file cert8.db to cert8.db.old in the Firefox Profile Folder to reset all root certificates. But it did not help. 1. My date and time is correct. 2. Save mode did not help. Anyone can help me please? Thank you

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sorry, this was a beginner mistake, I did not restart Mozilla... Now the renaming of the file cert8.db to cert8.db.old in the Firefox Profile Folder indeed worked. thank you

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Chosen Solution

sorry, this was a beginner mistake, I did not restart Mozilla... Now the renaming of the file cert8.db to cert8.db.old in the Firefox Profile Folder indeed worked. thank you