by Andrea Bicciolo.
Hi,
sometime we faced issues when using Exchange as authenticated SMTPserver from within Moodle and in most cases we found the Sender Policy Framework setup in Exchange to be the problem. Simply put, if you authenticate SMTP from Moodle against Exchange using a given user/pass, Exchange may refuse to send emails with a "from" address different from the email of the user used for SMTP authentication, and that may be very often the case with mails from Moodle, for example when using forums.
You should easily spot if the above is your case either following Howard's suggestions or checking your Exchange log.
sometime we faced issues when using Exchange as authenticated SMTPserver from within Moodle and in most cases we found the Sender Policy Framework setup in Exchange to be the problem. Simply put, if you authenticate SMTP from Moodle against Exchange using a given user/pass, Exchange may refuse to send emails with a "from" address different from the email of the user used for SMTP authentication, and that may be very often the case with mails from Moodle, for example when using forums.
You should easily spot if the above is your case either following Howard's suggestions or checking your Exchange log.