As your browser downloads pages from the cache, it may cache obsolete pages. The most straightforward and apparent reason why the invalid certificate error appears on a website is that the site has changed its domain. If you see such notice frequently here’re some ways to get your Mac to trust a certificate and fix the problem. One common cause of the warning can be incorrect date & time on Mac – authenticating a certificate requires your Mac’s clock to be synced with the clock on the server.Īlso, if a specific website changes the server, but your browser has cached the old server details, that can cause a warning pop up. You can either ignore the warning, inspect the certificate, or abandon the attempt to connect. If the certificate is not valid or expired, your Mac will display this warning.
macOS must check the certificate before it connects to any website. So no panic! Keep calm and keep reading! Why does Mac display an invalid certificate warning?Ĭertificates form part of the HTTPS protocol and are issued by an authorized certificate authority.
This article aims to show you what to do when you see such a warning. If it happens on almost every website you visit, it becomes a severe inconvenience. If it happens once or twice, it’s not too much of a problem. If the certificate for that connection has expired or is invalid, macOS warns you about that and asks you to choose to continue, inspect the certificate, or cancel. The certificate in question is the one used by Mac to validate the connection you are trying to make to a server. When you visit some websites on your Mac, you might have noticed that you get a warning that says, “the certificate for this server is invalid,” and asks you what to do next.
But to help you do it all by yourself, we’ve gathered our best ideas and solutions below.
So here's a tip for you: Download CleanMyMac to quickly solve some of the issues mentioned in this article.