> Source: [sk106970](https://support.checkpoint.com/results/sk/sk106970)

# sk106970 - "Unable to find valid certification path to requested target" error in SmartEndpoint when checking connectivity with Email Server

| Property | Value |
|----------|-------|
| Solution ID | sk106970 |
| Date Created | 2015-12-01 |
| Last Modified | 2020-07-07 |
| Technical Level | General |
| Products | Endpoint Security |
| Versions | Cloud, E89.X, E88.X, R82.10, R82, R81.20 |
| OS | Windows, Gaia |

## Symptoms

- * In SmartEndpoint, go to "Manage" menu - click on "Email Server Settings" - select "Configure settings" - enter the required information - click on "Check Connectivity" - operation fails with:

  ```
  
  SMTP Error: Could not convert socket to TLS
  Unable to find valid certification path to requested target
  ```

* *$UEPMDIR/logs/server_messages.log* on Endpoint Security Server shows the following error:

  ```
  
  [YYYY-MM-DD HH:MM:SS,NNN] ERROR Dispatcher-Thread-4 - Failed to send Alert email notification. (root)
  com.checkpoint.uepm.UEPMException: Failed to send Alert email notification.
  	at com.checkpoint.uepm.emon.dal.util.EmailNotificationHandler.processEvent(EmailNotificationHandler.java:68)
  	at com.checkpoint.uepm.sys.util.HandlerQueue$Worker.run(HandlerQueue.java:128)
  Caused by: com.checkpoint.util.mail.MailMessageFailedException: javax.mail.MessagingException: Could not convert socket to TLS;
    nested exception is:
  	javax.net.ssl.SSLHandshakeException: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
  ```

## Cause

SmartEndpoint / Endpoint Security Server does not recognize the CA (Certificate Authority) that signed the certificate used on the SMTP Email Server (e.g., this is a self-signed certificate).

## Solution

* Follow [sk84620 - How to configure Endpoint Security Server to connect to DC via LDAPS](https://supportcenter.checkpoint.com/supportcenter/portal?eventSubmit_doGoviewsolutiondetails=&solutionid=sk84620) to export certificate from SMTP Email Server and import that certificate to keystore of Endpoint Security Server.
* The correct certificate is the one where the ISSUER is a hostname of your mail server.

**Example:**   
If you e-mail server hostname is exchangehost.domain.com  
Search for a certificate according to sk84680 where:  
*ISSUER:*   
*CN=EXCHANGEHOST*

---

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