Configure Exchange 2013 to send external email
So you’ve just installed Exchange 2013 and you can’t send emails to other domains? No problem. Similar to Exchange 2010 (instructions found here), Exchange 2013 is installed without a default send connector enabled. In order to send emails to other Exchange servers or external domains, you’ll need to set it up. Follow the steps below to setup a send connector that will enable email to be sent to all external domains.
1. Login to the Exchange Control Panel: https://FQDN/ecp (or localhost, or IP address) internally or using the external IP or Domain externally. (Security tip: don’t use the default “administrator” account in production…I only did this for testing)
2. Go to Mail Flow and Send Connectors. Click the + (plus) button to add a new external send connector.
3. Give it a name, such as “External Email Connector” and select Type: Internet. Click Next.
4. Select “MX record associated with recipient domain” for sending email, unless your ISP or Host requires the use of Smart Hosts. Click Next.
5. Press the + (plus) button to add a new Address Space.
6. Under Type enter SMTP and under Cost enter 1. Under FQDN enter *. This ensures you can send email to all Internet domains. If you want to restrict which domains you can send email to, create a new Address Space for each domain, putting the domain name in the FQDN field. This is a useful feature for companies that require high security and control of emails being sent out (Government, Financial, Insurance). Click Next.
7. Click Next.
8. Press the + (plus) button to add a new Source Server (if you are running only one exchange server, this will be the current/transport server).
9. All exchange servers in the organization will be listed. Highlight the one you wish to use for transport, and click Add. Click OK.
10. Click Finish.
11. Now we need to set the FQDN for the server sending external emails. Highlight the External Email Connector you just created. Click the Edit button above.
12. Click on Scoping, scroll to the bottom and enter the FQDN of your server. This will likely be domainname.com or match your MX record (email.domainname.com). Click Save. This is an important step as it will decrease the likelihood your organization’s email being flagged as spam, by properly identifying your server to others. Exchange 2013 is now setup to send external emails properly.