If you are moving servers or providers, you will need to export the certificate and private key from the old server or provider. You can then use this to install your SSL certificate onto your new server or send on to your new host.
IIS users can use our describtion (https://secure.europeanssl.eu/en/kb/install/how-do-i-copy-or-transfer-an-ssl-certificate-from-a-windows-server-to-another-windows-server) in order to move a certificate from one IIS to another.
Please note: Without the corresponding private key there is unfortunately no possibility to transfer an SSL certificate from a server to a new server. If you no longer have the PrivateKey, you can simply reissue it free of charge using your customer account. First generate a new CSR on your web server or via our CSR generator (https://secure.europeanssl.eu/de/info/generator). Then log into your account, go to the certificate details and click on the "Modify" button. In the window that appears, you can add the new CSR and initialize the reissue. After successful validation, the certificate will be reissued.