SAP supports sending/receiving mail via MS exchange server.
You will have configure the SMTP server (MS exchange server) details using SCOT.
Refer the links below
This error comes because there are is no route maintained under the address area in the SMTP node in transaction SCOT.
Under the address area please enter the domains you would like to send mails to or if you would like to send to all domains enter the wildcard '*'
Please test again after this change and contact me with the results. Thank you!