> Source: [sk109240](https://support.checkpoint.com/results/sk/sk109240)

# sk109240 - "Endpoint Security Client cannot register to the server. The Security ID of this machine was not found." message in the newly installed Endpoint Security Client GUI

| Property | Value |
|----------|-------|
| Solution ID | sk109240 |
| Date Created | 2015-12-23 |
| Last Modified | 2017-03-15 |
| Technical Level | Advanced |
| Products | Endpoint Security |
| Versions | Cloud, E89.X, E88.X, R82.20, R82.10, R82, R81.20 |
| OS | Windows |

## Symptoms

- * "`Endpoint Security Client cannot register to the server. The Security ID of this machine was not found. Please contact your administrator`" message in the newly installed Endpoint Security Client GUI.

* The CPDA log from the Endpoint Security Client shows:

  `
  Startup: Endpoint not registered yet (CDA::doRegister)
  `  

  `
  Server authentication response header is empty. (CclientAuth::getAuthHeader)`  
  `
  Authentication is required. (CclientAuth::isAuthRequired)`  
  `
  Number of interactive sessions is: 1 (CclientAuth::getAuthHeader)`  
  `
  Authenticate by device. (CclientAuth::getAuthHeaderByType)`  
  `
  ---ERROR--- No authentication principals is found. (CclientAuth::getAuthHeader)`  
  `
  ---ERROR--- Kerberos authentication failed. (CclientAuth::getAuthHeader)`

## Cause

Kerberos Authentication is enabled on the Endpoint Security Server but it is not configured correctly.

Since this is a new client install, the client is unable to register on the Endpoint Security Server.

## Solution

This solution requires authentication. Please log in to view the full solution.

---

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