> Source: [sk110813](https://support.checkpoint.com/results/sk/sk110813)

# sk110813 - Anti-Spam blade sends Non-Delivery Report (NDR) when Mail Transfer Agent (MTA) is enabled on Security Gateway

| Property | Value |
|----------|-------|
| Solution ID | sk110813 |
| Date Created | 2016-04-25 |
| Last Modified | 2019-02-16 |
| Technical Level | Advanced |
| Products | Security Gateway |
| Versions | R82.10, R82, R81.20 |
| OS | Gaia |

## Symptoms

- If spam e-mail is blocked by the Anti-Spam blade, then a Non-Delivery Report (NDR) is sent to the e-mail sender when Anti-Spam and Mail Transfer Agent (MTA) are both configured on the Security Gateway.

## Cause

Check Point [Mail Transfer Agent (MTA)](https://supportcenter.checkpoint.com/supportcenter/portal?eventSubmit_doGoviewsolutiondetails=&solutionid=sk109699) uses [Postfix](http://www.postfix.org/) mail server. The default behavior of postfix is to send an NDR for mail that cannot be delivered. This includes mail that is blocked by the Anti-Spam blade.

## Solution

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