> Source: [sk153312](https://support.checkpoint.com/results/sk/sk153312)

# sk153312 - Emails are stuck in queue, "451 Retry later" error

| Property | Value |
|----------|-------|
| Solution ID | sk153312 |
| Date Created | 2019-07-15 |
| Last Modified | 2019-07-17 |
| Technical Level | Advanced |
| Products | Email Security |
| Versions | Cloud |
| OS | Gaia |

## Symptoms

- * Email are stuck in Postfix with the following error: "`451 Retry later.`"


  ![](https://sc1.checkpoint.com/sc//SolutionsStatics/sk153312/Stuck1907150149.PNG)
* The issue occurs for specific emails that have no body.

## Cause

The parser fails to scan the email because the email does not have a body.

This behavior is in line with the fail mode configuration: If it is configured as fail close, the emails are moved to the defer queue and later rejected.

## Solution

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

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