this is a simple guide for people need help how to request a certificate from the your Certification Authority.
The steps are the same for any of the services in the Exchange , but for this guide I’m going to be talking about the UM-Service.
Log into Your Exchange Server which you want to issue the Certificate to
open the EMC
1- Under “Server Configuration” in the Action Panel “Right Side” click on “New Exchange Certificate”
2- Give the Certificate a friendly name like “contoso-UM” and click Next
3-in the Domain Scope Page click Next
4- in the Exchange Configuration Page expand the Unified Messaging Server and Check the “Public Certificate” box and type the FQDN of your UM server.
this is the step you can configure the Certificate to the Services you want to use the certificate for like OWA , Autodiscover…etc.. our case it is UM
5-In the “Certificate Domain” page add the UM-Server or the Name of the Exchange Server that is hosting this role
6- In the “Organization and location” Page fill the required information and browse to a place where you going to save the .req file to submit it to the CA later
this can be done by just creating a text file on the Desktop with the name of your certificate like “contoso-UM.req”
7-in the “Certificate Configuration” Page click “New”
8- in the Completion Page click “Finish”
9- in the “contoso-UM.req” file created by the Exchange open it and copy the content between the Two lines
10- Now log into your CA using the IE or any method you like and click on “Request a Certificate”
11- next Page click on “Advance Certificate Request” then click on “Submit a certificate request using a base-64-encoded CMC or…….”
12- in the Next Page past the content of the contoso-UM.req file into the Based-64-encoded Certificate Request Box and click submit
13-in the next page click “download Certificate” and save the certificate on your Desktop “Contoso-UM.cert”
14-Now go back to the EMC select the UM-Server from the menu and click on “Complete Pending request” in the Action Menu.
15- Browse / Select the “contoso-UM.cert” file
16- Next Page click Finish
17- now time to assign the Certificate for a service, select the certificate and then in the Action Panel click on “Assign Services to Certificate”
18-In “Select Server” Page , add the Server you want to assign the certificate to “Exchange-UM Server” in our case
19-In “Select Service” page , select the services you assigning this certificate to ” Unified Messaging” in our case
20- In “Assign Services” Page, click “Assign”
21- in the “Enable Certificate with Thumbprint” pop up box click “Yes”
By this you are done requesting and assigning Certificate to UM service.