SMTP Telnet Test
Jul 23, 2015Dan Iverson
We are standing up a new data center and users received SMTP errors while testing. We were able to ping the server so DNS lookup and network traffic was working. But we only had a generic SMTP error message. So, I fired up telnet and tested our SMTP connection using these commands:
telnet
o smtp.psadmin.io
ehlo
mail from:[email protected]
rcpt to:[email protected]
data
Test Email
.
When we first tested send emails through the SMTP server, we received an “Unable to relay for [email protected]” error. That’s much more descriptive and a useful message to send to the Exchange administrators.
Note: This was originally posted by Dan Iverson and has been transferred from a previous platform. There may be missing comments, style issues, and possibly broken links. If you have questions or comments, please contact [email protected].
