Hi lccabeliza, glad to see you on Mozilla Support Forum. You have 2 Solutions:- '''Change the SSL Setting of Your Firefox browser''' * The first thing you need to do is type in the address bar of your Firefox browser the command “About:Config”. * A pop-up box should show up with the warning “This might void your warranty!” click on the option I accept the risk! * In the search box that comes up, type the words “security.ssl.enable_ocsp_stapling”. * The value of the new result that pops up will indicate “true.” Double click on the value to change it to “false”. * Try connecting to the website that you are trying to visit and see if this has fixed the error. If this doesn’t work, go to the next solution. '''The Proxy Setting of Your Firefox Browser''' When the proxy setting of your computer is not properly set to surf the internet, then you might also get this error. To solve this problem, please consider below steps. * On our Firefox menu bar, navigate through Tools Menu and click on the option tab. * On the new page that shows up, navigate to advance panel and click on the tab that is labelled Network. * In the connection field that is open, click on the button labelled as Setting. * A new pop-up box should appear on your screen with the title Connection Setting. * In the connection window that you now have opened, look for Manual Proxy Connection and check if it is selected. * If the Manual Proxy Connection is selected, then it means you will have to verify all the protocol fields by yourself. However, if you are not sure what to do about anything in this window, it is strongly recommended that you contact your network administrator. * If the Manual Proxy Connection is not selected, then leave it as it is and close the Connection Setting Window and call your network administrator. Finally, you should check If SSL is installed properly or not. If SSL is not configured properly then it may throw such type of error. Moreover, you should update the Firefox timely as new updates may revoke old algorithm support or other security changes. If it doesn't solved your problem, then feel free to ask in Reply Section. Thanks for raising your question in Mozilla Support Forum.