> Source: [sk93605](https://support.checkpoint.com/results/sk/sk93605)

# sk93605 - 'Forbidden encoding on composit mime type' log when e-mails are blocked by Security Gateway

| Property | Value |
|----------|-------|
| Solution ID | sk93605 |
| Date Created | 2013-07-18 |
| Last Modified | 2015-01-14 |
| Technical Level | Advanced |
| Products | Security Gateway |
| Versions | R82.10, R82, R81.20 |

## Symptoms

- * '`Reason: Forbidden encoding on composit mime type`' Reject log for SMTP traffic from IPS in SmartView Tracker.  

* '`Forbidden encoding on composit mime type`' messages in `$FWDIR/log/asmtpd.elg` log file on Security Gateway.

## Cause

The SMTP Security Server cannot inspect "composite encoding" MIME types. Therefore, by default, Security Gateway blocks such e-mails.

Possible reasons for this log:

* IPS protections for MIME enforcements are enabled
* Value of global attribute '`smtp_composite_encoding`' is set to '`false`' in the database on Security Management Server

## Solution

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