WWW prefix on my domain is not working... how to fix it?

Shopify Discussion

Topic summary

Main issue: The site loads without the WWW prefix, but www.domain fails. The domain provider (IONOS) attributes this to an SSL certificate problem and says it must be fixed by the hosting provider (Shopify) or the IP owner, ensuring the SSL covers subdomains/WWW.

Key technical points: SSL certificates secure HTTPS connections; the WWW prefix is a subdomain. A DNS CNAME record typically routes the www subdomain to the correct host, which is necessary for proper resolution and SSL coverage.

Latest update: A responder asked whether a CNAME record for “www” is set in the domain’s DNS. No confirmation or configuration details have been provided yet.

Actions suggested/implicit: Verify DNS settings to ensure a CNAME exists for the WWW subdomain. Coordinate with Shopify to ensure the SSL certificate is applied to the WWW subdomain, or with the IP owner if needed, as advised by IONOS.

Status: Unresolved and ongoing. The key open question is whether the WWW CNAME record is present and correctly configured, and whether SSL is provisioned for that subdomain.

Summarized with AI on January 4. AI used: gpt-5.
1

How can you ensure that your SSL certificate is also applied to subdomains or the WWW prefix?

The WWW prefix is not working on my website but the website without the prefix is working

My domain provider IONOS said that:

"we have identified an issue with the SSL certificate associated with your domain. This matter needs to be addressed either by your hosting provider [which is Shopify] or by the owner of the IP address. Upon review, it’s crucial to ensure that your SSL certificate is also applied to subdomains or the WWW prefix.

Please help, as my customers are having difficulty finding us.

Thanks,

S

2

Hey @sergiopagani ,

do you have the CNAME record set up in your DNS settings?