> Source: [sk113272](https://support.checkpoint.com/results/sk/sk113272)

# sk113272 - SSL Network Extender unable to establish VPN with Gateway using application mode

| Property | Value |
|----------|-------|
| Solution ID | sk113272 |
| Date Created | 2016-09-08 |
| Last Modified | 2016-09-15 |
| Technical Level | General |
| Products | Security Gateway |
| Versions | R82.10, R82, R81.20 |
| OS | Gaia |

## Symptoms

- * SSL Network Extender (SNX) client is unable establish the VPN tunnel with Gateway using application mode.
* Connect dialog box on SSL Network Extender (SNX) client disappears a few seconds after 'Connect' button is pressed.

## Cause

The SSL Network Extener (SNX) software product conflicts with the Sophos Antivirus running on the client. Specifically the Sophos AntiVirus Web Monitor intercepts all connections to the the localhost TCP port 7777, which is used by the *Staproxy.exe* component.

## Solution

Add an exception for localhost TCP port 7777 on the Sophos Antivirus Web Monitor.

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