Some traffic filtering or monitoring products may replace a webpage’s certificate with their own to intercept encrypted connections and trigger errors on secure sites like SEC_ERROR_UNKNOWN_ISSUER.
This may let the software place its certificate to the Firefox trust store again. If you don’t want to uninstall the software, just reinstall it. You should uninstall the third-party software and use the security software offered for Windows by Microsoft, for example, Microsoft Security Essentials (for Windows 7) and Windows Defender (Windows 10/8). If you have installed a third-party antivirus program on your computer before, perhaps the issue is caused by the software since it can interfere with Firefox's secure connections. Option 2: Disable the Interception of Secure Connections
Restart your PC and open the website again to see if SEC_ERROR_UNKNOWN_ISSUER is solved. If this cannot detect the virus, try another antivirus program like Malwarebytes.Īfter the scan, remove the virus.
Just try Windows Defender if you are running Windows 10. Thus, running a virus scan for your entire Windows system could be helpful.
If a virus is preventing the certificate from being detected, the error code may occur. So, how can you fix the error code? Here is something you can do! Firefox SEC_ERROR_UNKNOWN_ISSUER Fix Option 1: Run a Virus Scan Additionally, if your computer is infected by malware or virus, it is likely that you also come across this error. This error code means the certificate is not unknown by Firefox and therefore it cannot be trusted by default. Sometimes you see the message “warning: potential security risk ahead” with the same error code. Usually, you get an error message showing “ your connection is not secure” with the error code sec_error_unknown_issuer. If it cannot be validated, Firefox can disconnect the connection to the web page. When using Firefox to visit a website, this browser will verify the certificate used by the website is valid. In this article, MiniTool Solution offers some possible and useful solutions to help you out. This indicates that the website is using an SSL certificate that was issued by an untrusted entity. Anyone been through this and have a resolution? I have searched all over and can't find much.When opening a web page in Firefox, you may receive the error code: SEC_ERROR_UNKNOWN_ISSUER. Internet Explorer and Chrome appear to be working just fine and trusting my cert. This constraint allows Firefox to recognize the root certificate as a trusted root authority. The certificate you upload must contain "basicConstraints=CA:TRUE" to work with Mozilla Firefox browsers.
I found this in the documentation but not sure how to check my cert or if even related. If I import the cert into Firefox then it breaks it even more and just says "Secure Connection Failed" The server might not be sending the appropriate intermediate certificates.Īn additional root certificate may need to be imported. The certificate is not trusted because the issuer certificate is unknown.
As a result, it is not possible to add an exception for this certificate. This site uses HTTP Strict Transport Security (HSTS) to specify that Firefox only connect to it securely. 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. However, this site's identity can't be verified.
Normally, when you try to connect securely, sites will present trusted identification to prove that you are going to the right place. You have asked Firefox to connect securely to, but we can't confirm that your connection is secure. I turned on HTTPS decryption today and doing some testing but having a hard time getting Firefox to work with any sites that require decryption.