> Source: [sk105564](https://support.checkpoint.com/results/sk/sk105564)

# sk105564 - SIP Call Transfer stopped working after upgrade to R77.20 / R77.30

| Property | Value |
|----------|-------|
| Solution ID | sk105564 |
| Date Created | 2015-04-06 |
| Last Modified | 2017-07-30 |
| Technical Level | Advanced |
| Products | Security Gateway |
| Versions | R82.10, R82, R81.20 |

## Symptoms

- SIP Call Transfer stopped working after upgrade to R77.20 / R77.30 (the call is dropped during the transfer).

## Cause

The inspection of SIP traffic was improved in R77.20. In case, the SIP answer message is "4xx", the data connection is closed.

## Solution

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

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