I found the following command from technet forum to stop spoofing in exchange 2013,
Remove-ADPermission <ReceiveConnector Name> –user “NT AUTHORITY\Anonymous Logon” –ExtendedRights ms-Exch-SMTP-Accept-Authoritative-Domain-Sender
Do i have to run this command on all the default receive connectors as shown below.
| Receive Connectors Name | Roles |
| Client Frontend mydomain | FrontendTransport |
| Client Proxy mydomain | HubTransport |
| Default Frontend mydomain | FrontendTransport |
| Default mydomain | Hubtransport |
| Outbound Proxy Frontend mydomain | FrontendTransport |
(I was not aware of exch 2013 forum so i had raised this issue in exch 2007 forum also)Please do advise.
Thanks.