> Source: [sk139013](https://support.checkpoint.com/results/sk/sk139013)

# sk139013 - "Different community ID, possible NAT problem (VPN Error code 01)" error message when VPN traffic dropped

| Property | Value |
|----------|-------|
| Solution ID | sk139013 |
| Date Created | 2018-10-26 |
| Last Modified | 2018-11-01 |
| Technical Level | Advanced |
| OS | Gaia |

## Symptoms

- "Different community ID, possible NAT problem (VPN Error code 01)" error message when VPN traffic dropped.

## Cause

This error indicates that traffic has been tagged for one community, however VPN routing states this traffic should be routed to a different community.

**This mismatch occurs when overlapping encryption domains are present.**

## Solution

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

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