After updating my Firefox, I could not open several sites, including Google.com, Twitter.com, Facebook.com, etc. I received the error – Your Connection is not ...

A lot of users are reporting that when they try to access a website or a local web server, they see SEC ERROR REUSED ISSUER AND SERIAL warning. This issue is usually ...

Hello, I recently installed Zen browser and ran into a TLS error connecting to accounts.microsoft.com. Zen does not believe the cert is valid due to Error code: SEC ...

Mozilla has halted the automatic updates to Firefox 65 as users are unable to browse web sites due to certificate errors. These errors are being caused by conflicts between various antivirus program's ...

When browsing the Web, sometimes you might encounter a sec_error_bad_signature error in Firefox. This issue will prevent you from visiting certain websites, so let ...

When I tried https://catalog.update.microsoft.com in FireFox, I got a "sec_error_unknown_issuer" error. Searching for that brought up this StackOverflow question ...