SSL / TLSChrome · Edge · Firefox
ERR_CERT_COMMON_NAME_INVALIDCertificate Name Mismatch
The SSL certificate doesn't match the domain you're visiting. For example, the cert is for "example.com" but you're on "www.example.com" and the cert doesn't cover "www".
Why this happens
- Certificate doesn't include the "www" subdomain
- Certificate was issued for a different domain
- DNS is pointing to the wrong server with a different certificate
- You were redirected to an IP or hostname not on the certificate
How to fix it
- 1
Try the URL with/without "www" — one may work
- 2
Check the actual domain vs what the cert covers using an SSL checker
- 3
If managing the site, issue a new cert that covers both www and non-www
- 4
Verify your DNS is pointing to the correct server
Diagnose it faster
Use our free tools to check whether the issue is on your end or the server's: