You can click the "Advanced" button to expand this section and show extra details. If the certificate is not trusted because no issuer chain was provided (SEC_ERROR_UNKNOWN_ISSUER) then click the blue error message to expand this section and show the certificate chain.

You can click "Copy text to clipboard" and paste this base64 encoded certificate chain text in a reply. That will allow us to details like the issuer of the certificate.

• https://support.mozilla.org/en-US/kb/troubleshoot-SEC_ERROR_UNKNOWN_ISSUER

• always be cautious when you get an 'Untrusted' error message
• never create a permanent exception without investigating the cause and only use this to inspect the certificate

Jesus Christ dude, did you even read the entire post or at least looked at attached sreenshot???? For the christ sake.

By the way this happeneds an ALL web pages! Not on just one or two!

The screenshot you posted shows a blue SEC_ERROR_UNKNOWN_ISSUER. You can click this link and Firefox will display the certificate chain. If you copy this chain to the clipboard and post it in a reply then we can check who issued the certificate and check for other possible issues.

See also:

• https://support.mozilla.org/en-US/kb/troubleshoot-SEC_ERROR_UNKNOWN_ISSUER

This shouldn't happen with the websites you mentioned, so you really need to follow the steps I posted and provide the certificate chain information.

cor-el said

The screenshot you posted shows a blue SEC_ERROR_UNKNOWN_ISSUER. You can click this link and Firefox will display the certificate chain. If you copy this chain to the clipboard and post it in a reply then we can check who issued the certificate and check for other possible issues. See also:

• https://support.mozilla.org/en-US/kb/troubleshoot-SEC_ERROR_UNKNOWN_ISSUER

This shouldn't happen with the websites you mentioned, so you really need to follow the steps I posted and provide the certificate chain information.

Thank you! This was much more helpfull. I am using buil-in windows defender and it didn't scanned for any malwares. I tried with 3rd party malware cleaner (advanced cleaner) and it detected some malware. After removal everything works great!

I am sorry for being so annoyed last night. I spent several hours scratching my head, try any solution found on the web and just getting crazy about it.

You should do a scan now and then. They like to sneak in.

This worked for me:

In Firefox, browse to the about:config page If prompted, click "I accept the risk!" to continue In Search bar above "Preference Name", type the word enterprise If value of security.enterprise_roots.enabled is "false", right-click the line and select "Toggle" The line should read: security enterprise_roots.enabled ... modified ... boolean ... true

Try to browse to a site such as Google When presented with the SEC_ERROR_UNKNOWN_ISSUER page, click the Advanced button Scroll down to the bottom of the page - you're searching for "Certificate chain:" Under "Certificate chain:", highlight everything from the LAST "-----BEGIN CERTIFICATE-----" the the LAST "-----END CERTIFICATE-----" Ctrl-C to copy text to clipboard Open a text editor (such as Notepad) and paste the text inside Save the file as Cert.cer (you may need to rename the file if Notepad appends ".txt" to the end of the filename)

Back in Firefox, click the "three bar" button at the top right of the screen Choose "Options" At left side of window that opens, click on "Privacy & Security" Scroll to the bottom of the page Click on the "View Certificates" button Make sure the Certificate Manager window that pops up has "Authorities" highlighted Click the "Import" button and select the file you saved ("Cert.cer" or whatever) In the window that pops up, check the box next to "Trust this CA to identify websites" Click the "OK" button, then click the "OK" button in the Certificate Manager window

You should be able to browse to other sites now If you have any problems, restart Firefox and try again