You need to log into the IPedge from a console session (SSH or physical screen/keyboard) and do a ping and tracert to the SMTP server to see if the IPedge can contact it successfully.
From the Vxxxxx.log it will show something like
12/03 10:24:05.659 DBG T3SRV: TEST_SMTP [email protected] [email protected]
12/03 10:24:05.688 ERR Connecting to 192.168.0.1:25: Operation now in progress
12/03 10:24:05.688 DBG ReadLine started
12/03 10:24:05.689 DBG Receive returned: 0
12/03 10:24:05.689 DBG T3SVR: Session ended.