> Source: [sk122183](https://support.checkpoint.com/results/sk/sk122183)

# sk122183 - "Connection contains real IP of NATed Address" error when Anti-Spam and MTA enabled, and the destination is 127.0.0.1

| Property | Value |
|----------|-------|
| Solution ID | sk122183 |
| Date Created | 2018-01-07 |
| Last Modified | 2018-01-07 |
| Technical Level | Advanced |
| Products | Security Gateway |
| Versions | R82.10, R82, R81.20 |
| OS | Gaia |

## Symptoms

- * SmartView Tracker log with reason "Connection contains real IP of NATed Address" is generated, when Anti-Spam and MTA are enabled.
* The destination in the log is 127.0.0.1 (localhost) and the log Product is "Security Server".

## Cause

Anti-Spam is inspecting the traffic before it reaches the MTA. NAT is being performed to localhost (127.0.0.1), as MTA enabled (On same machine), which causes Security Servers to see the traffic as localhost to localhost (Violation).

## Solution

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