Is anyone familiar with Exchange SMTP authentication ?
Is that true, in the LAN (log on to domain), mail client doesn't need SMTP authentication to send mail by mail server?
We have a scanner/copier/printer combo (SAVIN 8035e). Without adding credential to its configuration it can email scanned files by using inside Exchange server 2003. This is not a computer. It doesn't log on to a domain.
We have a backup software (SyncBack) on a XP computer. It can also email notice without credential added.
We also have a Filemaker server on a Windows 2003 server, which can send email notification, without SMTP authentication enabled.
Strange thing is here,
When we use "telnet mail-server 25" (without AUTH LOGIN) to test mail on any inside computers, it seems fine and says mail is sent to query. But, recipient never receives the mail. Where does the mail go?
But if we use "telnet mail-server 25" with AUTH LOGIN, recipient CAN receive the mail. From here, it looks like SMTP authentication is needed.
Can anyone explain this behavior? We like to know how to control this mail authentication because we have a PHP script, which cannot use/add credential. It means the script doesn't work now.
Thanks for any help !