# H323 VoIP Calls are dropped

**Product**: Security Gateways  
**Version**: R81.20, R82, R82.10  
**Last Modified**: 2026-07-23

## Symptoms

- The H.323 VoIP call establishes successfully, audio starts, then call drops after ~30-60 seconds
- The traffic is: H.323 (TCP 1720 + dynamic high TCP/UDP ports)
- Gateway logs show: `Illegal H.225(Q931) No Q.931 User-user IE found`, for example:

## Cause

In a specific scenario the H.323 protocol inspection path classifies valid H.225 (Q931) messages as non-compliant.

## Solution

This problem was fixed. The fix is included in:

- [Jumbo Hotfix Accumulator for R82.10](https://sc1.checkpoint.com/documents/Jumbo_HFA/R82.10/Default.htm) starting from Take 19
- [Jumbo Hotfix Accumulator for R82](https://sc1.checkpoint.com/documents/Jumbo_HFA/R82/Default.htm) starting from Take 103
- [Jumbo Hotfix Accumulator for R81.20](https://sc1.checkpoint.com/documents/Jumbo_HFA/R81.20/Default.htm) starting from Take 158

If you choose not to upgrade, Check Point can supply a **Hotfix**. [Contact Check Point Support](https://www.checkpoint.com/support-services/.contact-support/) to get a Hotfix for this issue.

A Support Engineer will make sure the Hotfix is compatible with your environment before providing the Hotfix.

For faster resolution and verification, please collect [CPinfo files](http://supportcontent.checkpoint.com/solutions?id=sk92739) from the Security Management Server and Security Gateways involved in the case.

**Hotfix installation instructions:**

Refer to [sk168597 - How to install a Hotfix](https://supportcenter.checkpoint.com/supportcenter/portal?eventSubmit_doGoviewsolutiondetails=&solutionid=sk168597).

#### NOTE

This solution has been verified for the specific scenario, described by the combination of Product, Version and Symptoms. It may not work in other scenarios.

## Article Properties

**Access Level**: General  
**Status**: Approved by TAC  
**Date Created**: 2026-01-26  
**Last Modified**: 2026-07-23