How to Set Up an FTP Site on SBS
Instructions
1Insert your SBS installation medium. Click the "Start" menu, then the "Control Panel" button. Double-click the "Add or Remove Programs" shortcut, then click "Add or Remove Windows Components." Click "Internet Information Services" under the "Components" section, then click the "Details" button.
2
Click to check the "FTP Service" box, then click the "OK" button to launch the install wizard. Click "Next" to install the FTP service from the SBS installation medium, then click "Finish" when everything is complete.
3
Launch "IIS Manager" from your "Programs" menu. Click the "FTP Sites" folder, then right-click the "Default FTP Folder" and click the "Properties" option in the context menu. Change the directory or transfer any files you want hosted on your FTP server into this directory.
Source...