A name mismatch error means the certificate that the server presented does not list the address you typed. The connection may be encrypted, but the browser cannot confirm that it reached the right site.
A certificate lists the names it covers. The browser compares the address in the bar with that list, and an address that is not on the list produces the error.
The certificate covers www.example.com but not example.com, or the other way round. A site on shared hosting may present the hosting company's certificate instead of its own.
A new subdomain was added without extending the certificate, or the address points to the wrong server after a move.
Open the certificate details and read the names it lists. Then compare them with the address that shows the error, including the version with and without www.
SSL Domain Detective lists the certificates your domains use, so you can see which names they cover. Open SSL Domain Detective
SSL Domain Detective is now available on the App Store.
Last reviewed: 2026-11-02
#SSL #TLS #Certificates #DomainExpiry #SysAdmin #MSP #iOS
This page gives general information and is not legal, financial or medical advice. [email protected]