Connecting another ISP email bouncing!!!!!!!!!!!

[ashok_kumar]

Dear Friends,

                     We are using FGT200D in our environment and have only one ISP connected in WAN1 and now have taken another ISP for redundancy.Connected  the same in WAN2 and configured.But the problem is that all mails from out side not receiving and also internally mails getting ,sending to outside it will bouncing.

1st ISPs public ip we are registered in Exchange server message club.Right now am shut down the wan 2 interface.Please help me solving this issue.

Many Thanks

Ashok