To generate a Certificate Signing Request (CSR) via a MMC certificate snap-in using Microsoft Windows, perform the following steps.

1. From Microsoft Windows, click Start.
2. In the Search programs and files field, type mmc.
3. Click File > Add/Remove Snap-in.
4. From the list of available snap-ins, select Certificates.
5. Click Add.
6. Select Computer account.
7. Click Next.
8. Select Local computer (the computer this console is running on).
9. Click Finish.
10. In the Add/Remove Snap-in window, click OK.
11. Save these console settings for future use.
12. Access your MMC snap in > right click the Personal folder.
13. Select All Tasks > Advanced Operations > Create Custom Request.
14. The CSR generation wizard will open > Click Next.
15. Select the option to Proceed without enrollment policy > Click Next.
16. Click Next at the PKCS # 10 window.
17. From the Details drop-down menu > Click Properties.
18. Enter a Friendly Name of your choosing.
19. Access the Subject tab > in the Subject name: Type: field add the following distinguish name values required for your CSR (CN, O, OU, S, L and C).
Example:
CN = Common Name: The registered organizational name that the certificate will be issued to and secure.
O = Organization: The registered organizational name the
certificate belongs to. If the company or department has an &, @, or
any other symbol using the shift key in its name, the symbol must be
spelled out or omitted, in order to enroll. For example: “XY & Z
Corporation” would be “XYZ Corporation” or “XY and Z Corporation”.
OU = Organizational Unit: The department within the organization.
S = State: The business registered state or province. Do not abbreviate the state or province name, for example: California not CA.
L = Locality: The business registered location/city (not the actual server location).
C = Country/region: The two letter ISO country code.
20. Click the Private Key tab > click the drop-down for Key options > select Key size: 2048 and check the option to Make private key exportable > Click OK.
Note: All Code Signing or Client (S/MIME) certificates must have a 2048 bit key size.
21. Click the drop-down for Select Hash Algorithm, under Hash Algorithm select sha256 > Click OK.
22. Click Next > Click Browse.
23. Select a location to save the CSR file. Enter a name for the file and clickSave.
24. ClickFinish.
25. The CSR file will be present at the location you saved and can be used to request a Code Signing or Client (S/MIME) certificate.

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