Renewal Ndes Certificate

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:
  • CertReq.exe -New Request.inf Certnew.req
  • CertReq.exe -Submit Certnew.req Certnew.cer
  • CertReq.exe -Accept Certnew.cer

See also