> Source: [sk157092](https://support.checkpoint.com/results/sk/sk157092)

# sk157092 - Phase-2 negotiation fails with "Reason: Wrong value for: Encapsulation Mode"

| Property | Value |
|----------|-------|
| Solution ID | sk157092 |
| Date Created | 2019-06-28 |
| Last Modified | 2021-04-15 |
| Technical Level | General |
| OS | Gaia |

## Symptoms

- * After upgrade to R80.x, Phase-2 negotiation fails with "Reason: Wrong value for: Encapsulation Mode".  

* In *ike.elg* , Main Mode packet 3 from peer, has NAT Discovery payload. Main Mode Packet 5 and 6 use UDP/4500 correctly. Phase-1 negotiation is successful, but phase-2 negotiation sometimes fails with NAT-T.  

* In *vpnd.elg* , you will see either (or both) lines:   
  \[tunnel\] transformsMatch: lst_first failed for trans2  
  \[tunnel\] GOT LIFE DURATION P2 (lifetype: (nil), pair- \>type: 1)

## Cause

Encapsulation Mode is matched only according to the VPN Community settings. However, it does not match Encapsulation Mode according to negotiation information from the peer gateway.

## Solution

This problem was fixed. The fix is included in:

* [Jumbo Hotfix Accumulator for R80.30](https://supportcenter.checkpoint.com/supportcenter/portal?eventSubmit_doGoviewsolutiondetails=&solutionid=sk153152) from Take 76
* [Jumbo Hotfix Accumulator for R80.20](https://supportcenter.checkpoint.com/supportcenter/portal?eventSubmit_doGoviewsolutiondetails=&solutionid=sk137592) from Take 117
* [Check Point R80.40](https://supportcenter.checkpoint.com/supportcenter/portal?eventSubmit_doGoviewsolutiondetails=&solutionid=sk160736&partition=Basic&product=All) and above

For **other [supported](http://www.checkpoint.com/support-services/support-life-cycle-policy/index.html) versions** , Check Point can supply a **Hotfix** . [Contact Check Point Support](https://www.checkpoint.com/support-services/contact-support/) to get a Hotfix for this issue.  
A Support Engineer will make sure the Hotfix is compatible with your environment before providing the Hotfix.  
For faster resolution and verification, please collect [CPinfo files](http://supportcontent.checkpoint.com/solutions?id=sk92739) from the Security Management Server and Security Gateways involved in the case.  

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