Question

I want to send mails from my exchange server . I have tried many things.

I see that webdav is not supported in later exchange versions.
Activesync need license to use it.

I was trying smtp, but smtp is disabled for most of the corporate accounts.

I am really stuck at this point.
Any guidance on how to go ahead would be really useful.

Thanks in advance

Answer 1

If your Exchange is Exchange 2010 and you have OWA access, you can see what mail FQDNs and ports are offered by your Exchange by clicking on the round question mark icon (?) in the upper right corner of OWA (next to “Options“), then clicking About.

Within the window that pops up, you will get information such as (this is from Office 365)

 External POP setting:
 Server name: pod51018.outlook.com
 Port: 995
 Encryption method: SSL External IMAP setting:
 Server name: pod51018.outlook.com
 Port: 993
 Encryption method: SSL External SMTP setting:
 Server name: pod51018.outlook.com
 Port: 587
 Encryption method: TLS

If you’re writing an app to send SMTP, it probably does not matter that your mail server is Exchange, as you won’t be using any Exchange-specific protocols. You would have to use ActiveSync to leverage Exchange features, otherwise you would be simply using POP3/IMAP4 as the retrieval method and SMTP for the sending method, all of which are standard protocols.

Your Exchange server (and correctly configured mail server) will probably have SMTP open relaying blocked, so you will more than likely either need the user to authenticate to the SMTP server. In addition to authentication, you will need to use the correct SMTP port that allows submission and/or relaying.

The ports would be:

• 25 – this should always be available if you just want to submit a message to a recipient of within that same mail system (not relaying).
• 465 – legacy secure SMTP (I don’t believe this one is widely used).
• 587 – authenticated SMTP (in Exchange 2010, this is called the Client Receive Connector, or something similar)
• ??? – custom port specified by the administrator?

For testing purposes, if the recipient of your test message is in the mail system that the SMTP server receives for, you can probably send a standard SMTP message over port 25, without authentication. This is basically what regular email from the Internet would be doing. Antispam systems may detect spoofing attempts however, so be aware of that possiblity and check any quarantines if you do not receive the test message.

This almost definitely will NOT work if you are trying to anonymously send to a recipient OUTSIDE of the mail system that the SMTP server receives for (i.e. relaying).

So in summary:

1. Find the open SMTP port (e.g. 587) for relaying
2. Check the authentication methods that it supports/requires and provide authentication
3. Submit message.

Or if sending to a recipient inside that mail system:

1. Properly format the SMTP message (sender, recipient)
2. Submit un-authenticated SMTP message to TCP 25
3. Check mailbox (look out for quarantining, just in case).

Another possibility (of which I have no experience with) is to use Exchange Web Services (if you have Exchange 2010/2013). See:

http://msdn.microsoft.com/en-us/library/exchange/aa563049(v=exchg.140).aspx