>>>Test machine in my office sends E-Mail perfectly using wwiipstuff. At client site they are using Small Business Server 2011 running Exchange Server 2010
>>>
>>>Clients machine will send an E-mail thru Outlook with no problems. But my program fails using what seems to be the same credentials.
>>>
>>>Are there known gotcha's with this setup?
>>
>>Their Exchange needs to be set to allow SMTP Relay from the IP address of the machine that is sending the mail.
>
>Thanks Bill. Working on that right now. They are reluctant to have an "open" relay for the 13 machines that need to send this E-Mail stuff
>
>Ken

BTW If wwIPStuff supports authentication, you can put the Exchange Admins' little minds to rest by requiring authentication..

http://www.petri.co.il/authenticated-or-anonymous-smtp-relay-with-exchange-2007.htm