> For the complete documentation index, see [llms.txt](https://help.security.gallagher.com/knowledge-hub/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.security.gallagher.com/knowledge-hub/products/cc-software/configure/identity-solutions-cardholders-and-ope/active-directory/active-directory-single-sign-on-troubl.md).

# Troubleshoot Active Directory single sign-on

Diagnose Active Directory Single Sign-On failures caused by missing or duplicate SPNs.

Almost every SSO fault is an **SPN registration or duplication problem**, diagnosed and fixed with the Windows **`setspn`** command.

In the examples, `FTServiceAccount` is the account the FT Command Centre Service runs under, and `SERVERNAME.domain` is the machine name and domain.

## 1. List the SPNs on the service account

`setspn -L FTServiceAccount`. If nothing is registered, the result is empty:

```
c:\Windows\system32>setspn -L FTServiceAccount
Registered ServicePrincipalNames for CN=<FTServiceAccount>,CN=Users,DC=<domain>,DC=local:
```

## 2. Register the SPN

Needs privileges, usually domain admin:

```
setspn -s GGLCCSvc/SERVERNAME.domain FTServiceAccount
```

Alternative if using Local System / Network Service: `setspn -s GGLCCSvc/SERVERNAME.domain Hostname`. On success:

```
Checking domain DC=<domain>,DC=local
Registering ServicePrincipalNames for CN=<FTServiceAccount>,CN=Users,DC=<domain>,DC=local
        GGLCCSvc/servername.domain
Updated object
```

![Command Prompt showing a successful setspn -s GGLCCSvc registration against the service account](https://328339335-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F6bM8WhlBE9BYizPWJaPN%2Fuploads%2Fgit-blob-9d9e8734c69978adf8730ef66f504d929e04b653%2FSECHUB-AD-SSO-09-setspn-register-success.png?alt=media)

## 3. Check for duplicates

`setspn -x`. Ignore duplicates unless they involve `GGLCCSvc`.

## 4. Delete an incorrect or duplicate SPN

`setspn -d GGLCCSvc/ComputerName Account_or_ComputerName`, then re-list to confirm and **reboot**:

![Command Prompt showing setspn -d deleting the GGLCCSvc SPN then re-listing to confirm removal](https://328339335-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F6bM8WhlBE9BYizPWJaPN%2Fuploads%2Fgit-blob-ea7030231b0e9fdcdcb81752e35cc130a23e4fea%2FSECHUB-AD-SSO-10-setspn-delete-verify.png?alt=media)

## Reference example

> ⚠️ **Image redaction needed before publishing (flagged 2026-07-29):** this screenshot shows test-lab server / domain / service-account values. Re-capture or blur before this page is pushed public.

![FT Command Centre Service "Log On As" the domain service account — showing the machine name, domain, and service-account login](https://328339335-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F6bM8WhlBE9BYizPWJaPN%2Fuploads%2Fgit-blob-9b527f68ed4a9bd0207faecdd2418eb8de9d0209%2FSECHUB-AD-SSO-08-server-domain-service-account.png?alt=media)

***

🔗 **Related**

* [Single Sign-On - Common Fault and Scenarios](/knowledge-hub/products/cc-software/configure/identity-solutions-cardholders-and-ope/active-directory/active-directory-single-sign-on-common.md). Error codes and logon-name mismatches.
* [Single Sign-On - Setting Up](/knowledge-hub/products/cc-software/configure/identity-solutions-cardholders-and-ope/active-directory/active-directory-single-sign-on-settin.md). How the SPN is registered.


---

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