> Source: [sk114675](https://support.checkpoint.com/results/sk/sk114675)

# sk114675 - Cannot access 700 /1400 SMB appliance via WebUI or SSH with "MSS clamping" enabled

| Property | Value |
|----------|-------|
| Solution ID | sk114675 |
| Date Created | 2016-11-27 |
| Last Modified | 2017-04-24 |
| Technical Level | Advanced |
| Products | Spark Firewall (Locally Managed) |
| Versions | R82.00.X, R81.10.X |

## Symptoms

- * No access to 700 /1400 SMB appliance WebUI or via SSH once the MSS clamping (`fw_clamp_tcp_mss` and `fw_clamp_vpn_mss`) is enabled and policy is installed.
* Issue does not take place on 600 / 1100 SMB device.
* Traffic monitor shows that Syn-Ack packet leaves the gateway and reaches the client. but client does not respond with ACK.

## Cause

Syn-Ack packet is generated with the wrong TCP checksum.

## Solution

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

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