Exchange 2010 to use Fully Qualified Domain Name Since

Hi All, I hope you can help me understand and resolve my issue.

Scenario: we have exchange 2010 that has an expiring SSL Cert.
                  we have renew the cert. in godaddy.com but needed to take the SAN with a .local parameter since they are not  
                  allowing it anymore. So now after all the cert request, completing the request and Assigning services to use the
                  cert. We end up with one issue.  Once a client computer opens outlook we are getting a security alert
                   message that says The name on the security certificate in invalid or does not match the name of the site.

my question is. : We know that we are getting this because the SAN "servername.domain.local" is not in the Cert
                               anymore. Since Cert. Auth. is Phasing it out.
                           
                                We would like to know what steps we need to do to get it straightened it out. I red some article from
                                godaddy.com on how to configure the exchange server to use FQDN using a shell but not sure what
                                it can cause after running the command.

                                I think if we can make our email clients to resolve name with one of the SAN in the Cert. we will be fine
                                but we don't know how to handle it.

any solution with brief explanation will be appreciated. thanks in advance