Hello @Bahram Maleki ,
Thank you for posting here.
I have done a test in my lab.
Configure "Enrollment Agent" certificate template.
1.Duplicate an "Enrollment Agent" certificate template, and give "domain users" group "Read" and "Enroll" permissions.
Certificate template display name is Enrollment Agent-1.
2.Issue this certificate template.
Daisy 11 requests certificate using certificate template named "Enrollment Agent-1".
3.Logon one client using domain user named daisy11.
4.Request certificate using certificate template named "Enrollment Agent-1" in user store.
Daisy11 is able to request certificate on behalf another user.
5.After that Daisy11 is able to request certificate on behalf another user (B\yu).
Because daisy11 has two certificates issued by "Enrollment Agent" certificate template, so it will prompt me to select one.
6.Select one certificate template for domain user (B\yu).
7.Selcet the user name(B\yu).
8.Daisy11 now request certificate for B\yu successfully.
From the error message, it seems there is no corresponding Enrollment Agent certificate in this current logged on user Store.
So please check:
1.Check if this current logged on user Personal Store has installed Enrollment Agent certificate using Enrollment Agent certificate template? If so, ensure this cert is not expired.
2.Check if this current logged on user Personal Store has installed Enrollment Agent certificate using Enrollment Agent certificate template? If there is no such certificate or such certificate has expired, this logged on user can request Enrollment Agent certificate using Enrollment Agent certificate template again, then request certs on behalf another users.
3.Find which user has already requested Enrollment Agent certificate using Enrollment Agent certificate template now. You can use the user account with Enrollment Agent certificate in his/her Personal Store to request certs on behalf another users.
Similar case.
Certificate services - request client certificates on behalf of another user?
https://social.technet.microsoft.com/Forums/windowsserver/en-US/ef1e7953-0e41-4465-becc-74305e18b32b/certificate-services-request-client-certificates-on-behalf-of-another-user?forum=winserversecurity
Reference
Enroll for Certificates on Behalf of Other Users
https://learn.microsoft.com/en-us/previous-versions/windows/it-pro/windows-server-2008-R2-and-2008/cc770802(v=ws.11)?redirectedfrom=MSDN
Hope the information above is helpful.
Should you have any question or concern, please feel free to let us know.
Best Regards,
Daisy Zhou
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