After you configure your Microsoft Windows Small Business Server 2003-based computer to send and to receive Internet e-mail, you cannot successfully send e-mail messages through the SmallBusiness Simple Mail Transfer Protocol (SMTP) connector. The e-mail messages remain in the outgoing mail queue.
But why?
By default your Microsoft Exchange Server will configure the SMTP connector to send emails directly to the recipient's mail server. However more and more ISPs (Internet Service Providers) are blocking direct SMTP traffic using port 25 in the attempt to cut down on spam.
The solution is to configure your Exchange server to use a Smart Host such as outMail. outMail is a secure outbound SMTP mail relay. In layman's term instead of your exchange server failing to send emails directly your server delivers the email to the outMail servers for them to deliver on your behalf.
Even if your ISP is blocking TCP Port 25, outMail supports alternative ports. Better still you can try the service for free with outMail10.
Setting up Exchange to use a Smart Host
Below is a list of knowledgebase articles to guide you on a step-by-step basis for setting up your Exchange Server Smart Host and Relay.
How to setup MS Exchange 2003 as a Smart Host
How to setup MS Exchange 2007 as a Smart Host
How to setup MS Exchange 2010 as a Smart Host
Want more information
More information can be found in the outMail section on outbound SMTP outbound mail relay services.
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Prolateral Consulting is in business to put your organisation back in control of your own Information Technology, specialising in information and messaging security, computer forensic services, and disaster recovery planing.
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