> Source: [sk104396](https://support.checkpoint.com/results/sk/sk104396)

# sk104396 - L2TP VPN connection on Windows clients does not work with CHAP

| Property | Value |
|----------|-------|
| Solution ID | sk104396 |
| Date Created | 2015-01-26 |
| Last Modified | 2015-01-28 |
| Technical Level | Advanced |
| OS | Gaia |

## Symptoms

- * When try to send VPN traffic through L2TP client to the Security Gateway using encrypted password (CHAP), the connection does not get established.
* When try to send VPN traffic through L2TP client to the Security Gateway using the non-encrypted password (PAP) connection is established

## Cause

Using CHAP or CHAP v2 is not supported for L2TP clients trying to connect to Security Gateway through the VPN tunnel.

The authentication between the L2TP client and the Security Gateway is not supported using MS-CHAP, but the authentication between the Security Gateway and RADIUS is supported, using MS-CHAP-V2.

## Solution

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

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