How to renew the self-signed certificate using Exchange 2010 console
Exchange Server 2010 introduced the certificate management through Exchange Management Console. In order to manage it, just expand Server Configuration and click on the required server on the left and on the bottom you will see certificates available for that server and at the Toolbox actions you will be able to all available options.
In this post we are going to renew the certificate created during the server installation. Let's click on Renew Exchange Certificate as shown in the figure above, and in the first wizard page we can select the services associated to the certificate.
The renew of the self-signed certiicate will overwrite the current certificate, the console requires a confirmation, just click Yes.
Then, a three step will be performed in background and the results will be displayed in the Completion page. Just click Finish and enjoy your new renewed certificate.
By the way, the process to renew the self-signed certificate using Exchange Management Shell was posted a long time ago but can still be used in Exchange 2010: http://msmvps.com/blogs/andersonpatricio/archive/2008/04/08/how-to-renew-a-built-in-certificate-in-exchange-server-2007.aspx