Often you need to test email and if it's working. With these commands you can test email flow at a very granular level to determine what's broken and where.

Scenario:
Your domain: mydomain.com
Domain you wish to send to: theirdomain.com

1. Determine the mail server you're sending to.

* Open a CMD prompt
* Type NSLOOKUP
> set q=mx
> theirdomain.com
Response:
Non-authoritative answer:
theirdomain.com MX preference = 50, mail exchanger = mail.theirdomain.com

2. Connect to their mail server


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