From the Exchange Management Shell command line, type the following:
New-ExchangeCertificate -GenerateRequest -KeySize 2048 -Path c:\E-TugraCSR.txt -SubjectName "c=US, l=YourLocalityOrCity, s=YourStateOrProvince, o=YourCompanyInc, cn=YourFirstDomain.com" -DomainName YourSecondDomain.com, YourThirdDomain.com -PrivateKeyExportable:$true
Although this command is too long to fit on one line here in your browser, you need to enter it into the management shell as one line. Of course, you need to replace the details listed in this sample command with the details of your own organization including your two-letter country code (c=), your city or locality (l=), your state or province (s=), and your organization legal name (o=).
Notice that the first domain name is listed inside the "-SubjectName" after "cn=" and additional domain names are later added after the -DomainName parameter with commas between the additional domain names. You can add as many additional domain names as necessary.
You will now find your new CSR file named E-TugraCSR.txt in the root of your C: drive. Open this file with a text editor such as Notepad and paste the entire contents of the file, including the BEGIN and END tags to the E-Tugra UC Certificate order form.