The internal SMTP server feature is deprecated but not removed on Microsoft Windows Server 2012, so when moving legacy applications from an older server, you can still install the internal SMTP under IIS 6 on Windows Server 2012 R2 to avoid using a separate Exchange Server. Here are the steps to install it.
Launch Server Manager.
On the Dashboard, click Add roles and features on the right pane.
Click Next > button to go to Installation Type (on left) and select Role-based or feature-based installation on the right and click Features on the left.
In a box under the heading Features, check SMTP Server. There will be a pop-out screen to add more services or features. Just click the Add Features button.
You will be shown a confirmation screen. Click the Install button. Click Close button when finished.
You can find the IIS 6 by going to the tile menu and pick the icon with the purple background as pictured.
Launch the IIS 6 Manager to configure the SMTP server.
The default location of your SMTP folders will be in C:\inetpub\mailroot. You can move these default directories to a different drive.
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