SMTP authentication - basic doesn't work, NTLM does

afarr

There are many mibuso posts about sending mails through SMTP in NAV.

We have NAV 2009 R2 on SQL (both Classic and RTC).
When SMTP Setup in NAV is set to NTLM Authentication, we can send emails without problem.

When we use Basic Authentication, and try sending mail to an address that is outside the domain, we get:

The SMTP mail system returned the following error: Transaction failed. The server response was: 5.7.1 <abc@external-email.com>: Relay access denied

The username and password specified in SMTP Setup are valid, and they are used successfully to send mail using Outlook, but in NAV we get that error.

The IT administrator temporarily removed all validations, thus making the Exchange server an open relay, and we still got the same error message.

What can we do about it?

I have a second question -- What credentials are used when sending mail with NTLM Authentication?

vaprog

I suppose NTLM authentication uses Windows user credentials (on the Navision Server likely the service user's).

Do you specify the foreign email address as SenderAddress?

afarr

Thanks for the reply.

I am using the foreign email as Recipient, not as Sender.
NAV (and our Exchange Server) allow any address to be used as 'Sender', even addresses that don't exist - it's only a caption that appears on the email.