SBS 2008: Installing IIS SMTP service breaks Mailflow

Exchange 2007 is not designed to co-exist with the IIS SMTP service on the same server. This is unlike Exchange 2003, which depends on IIS to provide the SMTP service. If you install the SMTP service on SBS 2008, you will cause a conflict that can result in the inability to receive incoming email from […]

Exchange 2007 is not designed to co-exist with the IIS SMTP service on the same server. This is unlike Exchange 2003, which depends on IIS to provide the SMTP service. If you install the SMTP service on SBS 2008, you will cause a conflict that can result in the inability to receive incoming email from the Internet. One symptom of this is the receipt of an NDR by external senders[…]

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