> Source: [sk182661](https://support.checkpoint.com/results/sk/sk182661)

# sk182661 - Machine certificate authentication stops working after upgrading VPN client to E88.41 and higher

| Property | Value |
|----------|-------|
| Solution ID | sk182661 |
| Date Created | 2024-09-16 |
| Last Modified | 2025-06-24 |
| Technical Level | Advanced |
| Products | Endpoint Security |
| Versions | E89.X, E88.X |
| OS | Windows |
| Platform | Open Server |

## Symptoms

- * After upgrading the VPN clients to E88.41 or higher, the machine certificate that worked before stops working.
* The client log file `trac.log` shows   
  `[IKE] MM4PacketHandler::acceptMMPacket: A matching certificate for the machine was not found. Continue without it.`

## Cause

Incorrect format of the certificate Subject is no longer allowed starting from version E88.41 and higher.

## Solution

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

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