GMS has rejected the message because it has been sent by a server which has been banned from communicating with GMS by the administrator.
In this case, session Undefined was receving a message from Undefined. The message was rejected with
If you wish to receive a message from this server, you will need to change the IP addresses allowed to communicate with GMS. The global variables that hold this information are IPAllowed and IPAllowedMes.
Keywords:SMTP ip allowed reject 8128