This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Hierdie gesprek is in die argief. Vra asseblief 'n nuwe vraag as jy hulp nodig het.

I receive error message "SEC-error_unknown_ISSUER". I have followed your support info. What now?

  • 4 antwoorde
  • 4 hierdie probleem
  • 18 views
  • Laaste antwoord deur Jerilynn

more options

I have followed your instructions, un-installed and re-installed twice. I have disabled virus/malware, firewall, you name it and I have probably tried it. It won't go anywhere, I get the same message wherever I try to go. Is this new version incompatible with win 10? Please help me, I don't want to use Chrome or IE. I miss my Firefox.........

I have followed your instructions, un-installed and re-installed twice. I have disabled virus/malware, firewall, you name it and I have probably tried it. It won't go anywhere, I get the same message wherever I try to go. Is this new version incompatible with win 10? Please help me, I don't want to use Chrome or IE. I miss my Firefox.........

All Replies (4)

more options

Since uninstalled.... Have you done it this way : uninstall Firefox. Then Delete the Mozilla Firefox Folders in C:\Program Files and C:\Program Files(x86) Then restart system. Then run Windows Disk Cleanup. (Note: This should be Pinned and run Weekly, If never done below expect 10's of gig's) Then run it again and click the button that says Cleanup System Files. Note: your Firefox Profile is saved. But you should make a back up before you do : https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles

https://support.mozilla.org/en-US/kb/export-firefox-bookmarks-to-backup-or-transfer

Reinstall with Current Release Firefox 57.0.2 with a Full Version Installer https://www.mozilla.org/firefox/all/

Please let us know if this solved your issue or if need further assistance.

more options

I followed your instructions and I am receiving the error message that says "Website not secure, it is configured improperly". I tried amazon, facebook, twitter, wikipedia and my home page all with the same result. Using Chrome is close to torture, you know that?

Gewysig op deur Jerilynn

more options

Who is the issuer of the certificate?

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.

  • 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
more options

The problem turned out to be my proxy settings, somehow they were changed. It is working beautifully, so if anyone else has this issue check your proxy settings. I am so happy I don't have to look at Chrome, IE or Edge again!!!!! Yippeeeee...........Thanks for your help and have a great day to all of you at Mozilla Love my firefox.