> Source: [sk121812](https://support.checkpoint.com/results/sk/sk121812)

# sk121812 - "Received compressed packet on an uncompressed connection" error message when traffic dropped for encryption failure

| Property | Value |
|----------|-------|
| Solution ID | sk121812 |
| Date Created | 2017-12-11 |
| Last Modified | 2022-09-06 |
| Technical Level | Advanced |

## Symptoms

- IPsec VPN tunnel was up and running, but suddenly the communication was broken for about 90 minutes. During this time, the user could see dropped traffic from the site with an encryption failure "Received compressed packet on an uncompressed connection. Sequence Number xxxxxx (Expected 0)".

## Cause

The Security Gateway receives a compressed packet, while expecting to receive an uncompressed packet.

## Solution

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

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