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iPad IPSec VPN - RSA Signature - ERROR: invalid authmethod 65005

Hi, Hoping someone can help out I have setup an IPSec VPN on Cisco SA540 using RSA-Signature however I am unable to connect the error I received on iPad is "Negotiation with VPN Server failed."

VPN Error:

[IKE] ERROR:  invalid authmethod 65005 why ?

[IKE] INFO:  Received Malformed packet of payload

VPN Config

IKE Policy:

Direction / Type: Responder

Exchange Mode: Main

Identifier Type:  FQDN


Encryption Algorithm: AES-128

Authentication Algorithm: SHA-1

Authentication Method: RSA-Signature

DH Group: Group 2

SA-Lifetime: 28800

Dead Peer Detection: Enabled

XAUTH Configuration: Edge Device

VPN Policy:

Remote Endpoint: FQDN -

Mode Config: Enabled

Remote traffic: Any

SA Lifetime: 3600

Encryption Algorithm: AES-128

Integrity Algorithm: SHA-1

PFS Key Group: Enabled

DH Group 2

VPN Log attached.

Everyone's tags (4)

iPad IPSec VPN - RSA Signature - ERROR: invalid authmethod 650

Hello nsweetman,

I have not seen other users using the RSA-Signature, so my assistance may be limited. I did find the following link which you can check if you would like.

To summerize, you should use Aggressive mode instead of Main mode.

If this change fails, you should be able to use the Pre-Shared Key method. If you need assistance with that, feel free post back.

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