> Source: [sk182991](https://support.checkpoint.com/results/sk/sk182991)

# sk182991 - Locally Managed R81.10.X  Spark Firewall does not forward emails over the POP3 protocol over the Bridge interface with VLAN interfaces

| Property | Value |
|----------|-------|
| Solution ID | sk182991 |
| Date Created | 2025-01-19 |
| Last Modified | 2026-05-03 |
| Technical Level | Advanced |
| Products | Spark Firewall (Locally Managed) |
| Versions | R81.10.X |

## Symptoms

- An internal email client does not receive emails over the POP3 protocol in this scenario:

1. Locally Managed R81.10.X Spark Firewall.
2. A Bridge interface is configured.
3. VLAN interfaces are configured on the Bridge interface.
4. An internal email client is connected to one of these VLAN interfaces.
5. Anti-Virus inspection of emails over the POP3 protocol is enabled.

## Cause

Starting from R81.10.00, MUX/CPAS is used for connection folding of email traffic instead of PSL. The specific topology of Bridge and VLAN does not work within the MUX/CPAS infrastructure.

## Solution

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

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