> Source: [sk104677](https://support.checkpoint.com/results/sk/sk104677)

# sk104677 - Site to Site VPN between two Check Point Gateways fails with "INVALID-EXCHANGE-TYPE" log 

| Property | Value |
|----------|-------|
| Solution ID | sk104677 |
| Date Created | 2015-02-11 |
| Last Modified | 2015-02-12 |
| Technical Level | Advanced |

## Symptoms

- * IKE.elg packet one dropped INVALID-EXCHANGE-TYPE
* IKE: Main Mode Sent Notification to Peer: Aggressive Mode is not supported
* IKE: Phase1 Received Notification from Peer: invalid exchange type
* IKE: Aggressive Mode Peer MAY not support Aggressive Mode

## Cause

The Aggressive Mode feature is enabled on one peer, while it is disabled on the other.

**Note:** As the Aggressive Mode feature is a "support feature" and not an "enforce feature", the tunnel can be negotiated from the peer on which the Aggressive Mode is not enabled.

## Solution

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

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