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Renewal of "Enrollment Agent" certificate used by NDES

Network Device Enrollment Service (NDES) requests two certificates according the following two certificate templates configured with the “Intended purpose” (Enhanced Key Usages) set to “Certificate Request Agent”:

  • CEP Encryption.
  • Exchange Enrollment Agent (Offline request).

To renew CEP certificate do the following:

  • Open MMC console and add certificates snap-in
  • Browse to the CEP certificate located in Personal certificates container
  • Right click and select All Task -> Advanced -> Renew
  • Follow the workflow using the CEP encryption template

To renew Exchange Enrollment Agent certificate:

Create a file named Request.inf with the following contents

Signature="$Windows NT$"
RenewalCert="<Certificate Hash>"

You can get the Exchange Enrollment Agent (Offline request) certificate’s certificate hash by copying the value of the certifiate’s “thumbprint” extension retriveved from certificate’s “Details tab”.

Note: MachineKeySet set to “True” so the certificate and its private key will be stored in computer certificate store.

  1. Run the following 3 commands to renew that old Enrollment Agent certificate:
  2. CertReq.exe -New Request.inf Certnew.req
  3. CertReq.exe -Submit Certnew.req Certnew.cer
  4. CertReq.exe -Accept Certnew.cer