Can I import an existing SSL certificate?

I have a client that has an existing SSL certificate. Im rebuilding his website and I dont want to use his existing server because its Windows based (Ill be building the site in PHP). Can I transfer his SSL certificate to another hosting provider? If so - who?

Yes, that is correct. I missed out the “windows” bit … maybe i need glasses …

SSL certificates are specific to the web server type being used. So if he was on a Windows server it was most likely an IIS server, so you’d need to find another host using that. Or, if the SSL provider allows it, you can re-issue the SSL for a new server type. Most SSL providers do that.

Yes, generally you can move the SSL if you have the certificate and the RSA key.