I have a client connecting to my VPN infra, for some reason they connect and for about 16 seconds get disconnected and receive an error "Secure VPN Connection Terminated by Peer: Reason:433".
I have searched on the net but couldn't find a helpful solution.

My thinking is that is something to do with VPN Client and the client OS because I simulated the connection on my laptop I did not receive an error and I have other clients using the same VPN but don't get the error.

This is the sample of the error log:
124 06:55:22.419 06/24/16 Sev=Info/4 IKE/0x63000013
SENDING >>> ISAKMP OAK INFO *(HASH, NOTIFY:DPD_REQUEST) to ***.***.***.***

125 06:55:22.429 06/24/16 Sev=Info/4 IKE/0x63000014 RECEIVING <<< ISAKMP OAK INFO *(HASH, NOTIFY:DPD_ACK) from ***.***.***.***

RECEIVING <<< ISAKMP OAK INFO *(HASH, DEL) from ***.***.***.***

129 06:55:23.651 06/24/16 Sev=Info/4 IKE/0x63000017
Marking IKE SA for deletion (I_Cookie=227ABC18A518AFF7 R_Cookie=514A00395D9AB90A) reason = PEER_DELETE-IKE_DELETE_UNSPECIFIED

130 06:55:23.921 06/24/16 Sev=Info/4 IPSEC/0x63700013
Delete internal key with SPI=0x3fde47dd

131 06:55:23.921 06/24/16 Sev=Info/4 IPSEC/0x6370000C
Key deleted by SPI 0x3fde47dd

132 06:55:23.921 06/24/16 Sev=Info/4 IPSEC/0x63700013
Delete internal key with SPI=0x467eea43

133 06:55:23.921 06/24/16 Sev=Info/4 IPSEC/0x6370000C
Key deleted by SPI 0x467eea43

134 06:55:24.422 06/24/16 Sev=Info/4 IKE/0x6300004B Discarding IKE SA negotiation (I_Cookie=227ABC18A518AFF7 R_Cookie=514A00395D9AB90A) reason = PEER_DELETE-IKE_DELETE_UNSPECIFIED

135 06:55:24.422 06/24/16 Sev=Info/4 CM/0x63100013
Phase 1 SA deleted cause by PEER_DELETE-IKE_DELETE_UNSPECIFIED. 0 Crypto Active IKE SA, 0 User Authenticated IKE SA in the system

136 06:55:24.432 06/24/16 Sev=Info/4 IKE/0x63000001
IKE received signal to terminate VPN connection

137 06:55:26.796 06/24/16 Sev=Info/4 CM/0x63100035
The Virtual Adapter was disabled



Any possible suggestions ???????????????????????????

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