Client and server don't support a common SSL protocol


I have setup a subdomain via CNAME entry and have pointed the DNS to “” as it is Google Site built page.

I have ensure that Cloudflare SSL is turned off as to not conflict with Google’s own SSL which is automatically applied for all Google site.

See error received when trying to open the site.

This site can’t provide a secure connection

site uses an unsupported protocol.


Unsupported protocol

The client and server don’t support a common SSL protocol version or cipher suite.

Anyone able to help what might be causing the issue?


Yet it’s still an HTTPS url that’s proxied by Cloudflare. Cloudflare SSL will have to be enabled for this. But with a subdomain that deep, it needs a special ACM certificate. Or just don’t put ‘www’ in front of it.

You were absolutely right! Issue was due to DNS proxy. I have disabled this just for the CNAME entry for the subdomain, and it has worked wonders!

Thank you so much.

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