Brother MFC-3420C - Manual (Page 106)

4 - 30 USING THE WINDOWS ® XP-BASED BROTHER SMARTUI CONTROL CENTER
2. Select Configuration for the Scan Type.
To configure the scan operation click on the Configuration Tab.
Depending upon which Scan Type button you selected you will see
a different Configuration Tab list of settings.
Application:
Select the destination application program from the pull down list.
Click on Link Preferences to set the Send to options. You can select
the application from the scroll menu on the left.