Question

Recently, you have installed Mozilla Firefox on your system. When you attempt to open any secure Website using HTTPS, you get the following error: SEC_ERROR_UNKNOWN_ISSUER What could be the probable cause? [Choose all that apply.] A) The certificate on your system is not trusted by Firefox. B) The certificate on your system is replaced with another certificate by malware. C) The certificate is self-signed. D) The certificate on your system is replaced with another certificate by an antivirus tool. E) The hostname used in the URL doesn't match the name on the certificate.

Answer 1

The SEC_ERROR_UNKNOWN_ISSUER error occurs when Firefox cannot validate a website's security certificate. This could be because the certificate is not trusted by Firefox, has been replaced by malware or an antivirus tool, is self-signed, or the hostname in the URL doesn't match the name on the certificate.

Step-by-step explanation:

The error SEC_ERROR_UNKNOWN_ISSUER in Mozilla Firefox is usually associated with a problem concerning the website's security certificate. This occurs when Firefox is unable to validate the certificate that the website has provided, due to one or more reasons. Possible causes include:

• A) The certificate on your system is not trusted by Firefox.
• B) The certificate on your system was replaced with another certificate by malware.
• C) The certificate used by the website is self-signed.
• D) The certificate on your system was replaced by another one due to an antivirus tool's activity.
• E) The hostname used in the URL doesn't match the name on the certificate.

By referring to these possible causes, you can apply appropriate solutions to rectify the error.

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