Navigate to your site’s home and select on ‘Server Certificates’ located under ISS
In the far right Actions pane, select ‘Create Certificate Request’
Fill out the Distinguished Name Properties form. This includes the following fields: Common name, Organization, Organizational unit, City/locality, State/province, and Country/region. Select Next
Leave the Cryptographic service provider and Bit length as default, then select Next
Save the .csr file to your local machine
Export the file in format .pfx using mcc
Go to Start -> Run and type ‘mmc’ to open the Microsoft Management Console
From the MMC menu bar and select File -> Add/Remove Snap-in
Select the Add button and select Certificates from the list. Select Add
Slect the Computer Account. Click Next, Close, and Ok.
Navigate to Certificate Enrollment Requests -> Certificates
Right click your previously created certificate and select All Tasks -> Export…
Choose Export with private key on the radio button options, select Next.
In the certificate export wizard select Personal Information Exchange - PKCS #12 (.PFX)
Set a password, Browse to where you would like to save your export, and click Next, then Finished
Convert .pfx to RSA private key format
Navigate to the downloaded location of the .pfx file using CMD
Type the following command to first convert the .pfx file to .pem