Redirects and HTTPS are a pretty dry subject. So I’ll keep it techie and brief. The definition of the problem comes from the desire to redirect global domains to a single version of the site. i.e. redirecting .com to .co.uk.
Although there’s a simple answer for the redirect of the HTTP version of the site (DNS records) the answer for redirecting the HTTPS reveals a couple of thoughts and implications.
Redirecting .com to .co.uk when .com hasn’t got an SSL certificate
Jumping into the crux of the issue. If the .com version of the site doesn’t have an SSL certificate installed, there isn’t essentially a website to redirect. Therefore redirecting https://myexamplewebsite.com to https://myexamplewebsite.co.uk would result in the following screenshot:
The short answer therefore is:
“If you want to redirect the HTTPS version of a domain name, the domain name you are trying to redirect needs to have an SSL Certificate installed”
Call it a no-brainer. It wasn’t instantly obvious, as redirects had been setup via DNS entries, but the HTTPS versions weren’t working.
Install SSL Certificate on .com version of domain
Bluehost provide free SSL certs for WordPress sites, so we’ll start there.
Here’s a good article with some more in depth detail on the subject