Here’s a possible scenario.
Let’s say I have a website “https://www.mywebsite.com” and there is a valid SSL certificate purchased for this domain.
I want to “mimick” this website on my LOCAL machine for a testing purpose.
So let’s say I set up a locally-configured “https://www.mywebsite.com” (which is in essence https://localhost/mywebsite or something similar).
Would I be able to re-use the SSL certificate on my local testing website?
You can re-use your SSL certificate if you configure your DNS so that your test machine is the same domain name as server, which is probably a bad idea.
You can also re-use it on your test machine if you don’t mind clicking the box “accept this whacked out ssl cert”… So I suppose that the answer is technically yes, although I wouldn’t personally do it.