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invalid security certificate issue

Like many, I'm receiving the following page:

"This Connection is Untrusted

You have asked Firefox to connect securely to **********, but we can't confirm that your connection is secure.

Normally, when you try to connect securely, sites will present trusted identification to prove that you are going to the right place. However, this site's identity can't be verified. What Should I Do?

If you usually connect to this site without problems, this error could mean that someone is trying to impersonate the site, and you shouldn't continue.

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

facebook.com uses an invalid security certificate.

The certificate is not trusted because the issuer certificate is unknown. The server might not be sending the appropriate intermediate certificates. An additional root certificate may need to be imported.

(Error code: sec_error_unknown_issuer)"

I have tried using the various solutions that you have on your troubleshooting page, and it hasn't worked or is not applicable. I currently use Kaspersky PURE 3.0, version 13.0.2.558 as my security. Thanks for your help.

Like many, I'm receiving the following page: "This Connection is Untrusted You have asked Firefox to connect securely to **********, but we can't confirm that your connection is secure. Normally, when you try to connect securely, sites will present trusted identification to prove that you are going to the right place. However, this site's identity can't be verified. What Should I Do? If you usually connect to this site without problems, this error could mean that someone is trying to impersonate the site, and you shouldn't continue. This site uses HTTP Strict Transport Security (HSTS) to specify that Firefox only connect to it securely. As a result, it is not possible to add an exception for this certificate. facebook.com uses an invalid security certificate. The certificate is not trusted because the issuer certificate is unknown. The server might not be sending the appropriate intermediate certificates. An additional root certificate may need to be imported. (Error code: sec_error_unknown_issuer)" I have tried using the various solutions that you have on your troubleshooting page, and it hasn't worked or is not applicable. I currently use Kaspersky PURE 3.0, version 13.0.2.558 as my security. Thanks for your help.

All Replies (4)

None of the solutions that you suggested work, I still receive the same page/response.

The "unknown issuer" code generally indicates a problem in the certificate chain. In other words, whatever certificate was used to validate the website's certificate does not link up with any certificates trusted by Firefox.

This can be caused by Firefox not being setup to work with your security software (e.g., Kaspersky, ESET, BitDefender, Avast) or by a malware infection.

In order to tell them apart, you want to look at the "Issued by" and "Certificate Hierarchy" in the certificate for one of the untrusted connections.

If you created an exception for a site, you can view the cert by clicking the padlock in the address bar, then More Information, then View Certificate.

If you did not create an exception but the page has an I understand the risks section, you can expand that and use the Add Exception button to view the certificate. You can cancel out without actually adding an exception after that.

I have attached comparison screen shots for this site and for my test page:

https://jeffersonscher.com/res/jstest.php

What issuer(s) are you seeing?

Oh, I didn't read to your last paragraph. Kaspersky PURE 3.0. See: http://support.kaspersky.com/us/9927#block1