On this site https://www.digicert.com/easy-csr/exchange2010.htm you can easily create a powershell command for a Exchange 2010 certifcate request (CSR).
Just fill in the appropriate names and the powershell command will be created. For the command name I always use the name of the Exchange receive connector.
Maybe you have a good alternative or script to create a CSR. Please leave a comment and share it with us!