SSL certificate is not working for subdomain with www

0
votes

We are running our website on IIS. In the domain settings, example.com and www.example.com are pointing to same IP Address.

The website works fine for https://example.com and https://www.example.com and https://stage.example.com

but for:

https://www.stage.example.com

We are getting Not Secure error.

Is it related to how SSL certificate is setup?

Added http & https bindings in IIS for both stage.example.com and www.stage.example.com

1
ssliis
It depends on what kind of certificate you use, as www.stage.example.com can fall out of the DNS names covered by that certificate. - Lex Li

1 Answers

1
votes

If you have a non-www and fully-qualified domain name of the same domain, a single domain (standard) SSL certificate would be enough to cover both. However, if you have multiple subdomains that you need to cover, then you need a wildcard SSL certificate.

For example:

Scenario 1: If you want to secure only two versions of your domains — domain.com and www.domain.com — a single domain SSL would be fine.

Scenario 2: If you want to secure the first level of subdomains (other than www.domain.com) — such as mail.domain.com or test.domain.com — a single domain SSL will not be enough. You must buy a wildcard SSL certificate