See below to revoke a certificate before its expiration date.

To revoke a certificate

1. Log in as an administrator with the required permissions. 

   See Browsing roles for the permissions granted to each ad administrator role.

2. Go to Control > Certificates.
3. In the main grid, click Select Action > Revoke for the certificate.

4. In the Revocation Reason list of the Revoke dialog, select the revocation reason. 

5. In the Comment field, add an optional comment on the revocation reason.
6. Click Save.