> Source: [sk27109](https://support.checkpoint.com/results/sk/sk27109)

# sk27109 - SmartView Tracker drop logs show "Invalid TCP packet - source / destination port 0" or "Invalid UDP packet - source / destination port 0"

| Property | Value |
|----------|-------|
| Solution ID | sk27109 |
| Date Created | 2004-09-16 |
| Last Modified | 2017-07-09 |
| Technical Level | Advanced |
| Products | Security Gateway |
| Versions | R82.10, R82, R81.20 |

## Symptoms

- SmartView Tracker logs show dropped TCP / UDP packets:

*

  ```
  
  Type: Log
  Action: Drop
  Protocol: tcp
  Information: message_info: Invalid TCP packet - source / destination port 0. Dropped although the protection is disabled
  ```

*

  ```
  
  Type: Log
  Action: Drop
  Protocol: udp
  Information: message_info: Invalid UDP packet - source / destination port 0. Dropped although the protection is disabled
  ```

*

  ```
  
  Type: Log
  Action: Drop
  Protocol: tcp
  Information: message_info: Invalid TCP packet - source / destination port 0. Dropped although the protection is in detect mode of activation
  ```

*

  ```
  
  Type: Log
  Action: Drop
  Protocol: udp
  Information: message_info: Invalid UDP packet - source / destination port 0. Dropped although the protection is in detect mode of activation
  ```

## Cause

By design, TCP / UDP packets with either source port 0, or destination port 0 are dropped.

## Solution

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

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