> Source: [sk148872](https://support.checkpoint.com/results/sk/sk148872)

# sk148872 - VPN Traffic drops due to decryption error "Tunnel is accelerated but packet was not decrypted by SecureXL" in an environment with PPPoE interface

| Property | Value |
|----------|-------|
| Solution ID | sk148872 |
| Date Created | 2019-03-16 |
| Last Modified | 2020-10-26 |
| Technical Level | Advanced |
| Products | Security Gateway |
| Versions | R82.10, R82, R81.20 |
| OS | Gaia |

## Symptoms

- VPN traffic over a PPPoE interface is not working when SecureXL is enabled.  
Running kernel debug (# fw ctl zdebug + drop) will show the following drop:   
`
dropped by vpn_ipsec_decrypt Reason: decryption failure: tunnel is accelerated but packet was not decrypted by SecureXL`

## Cause

SecureXL does not support Point-to-Point interfaces (PPP, PPTP, PPPoE). If a PPP-interface is detected, SecureXL disables itself on that interface (hence the name 'non-accelerated interface').

SecureXL cannot be 'disabled' in R80.20 and above, as in previous versions.

## Solution

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

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