When you change your hosting service, believe that your CSR/RSA pair has been compromised, or replace the domain name(s) for which the SSL was issued, you need to have your SSL encryption certificate reissued. Changes to contact details in the certificate may require a reissue, as well. To begin the process, you must generate a new CSR/RSA pair and save your RSA for further installation. Be sure to save your RSA for later steps in the installation. This can usually be done by the user, but your hosting provider may be able to assist.