Solution
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MF Toolbox
1. Select where the document is placed in [Select Source].
(A): Select Source
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ScanGear MF
1. Select where the document is placed in [Select Source].
(A): Select Source
1. In [Original Input Method], select where the document is placed from [Platen Glass] or [ADF (1-sided)].
(A): Original Imput Method
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WIA Driver
1. In [Paper source], select where the document is placed.
(A): Paper source
1. In [Source] in the [New Scan] Dialog Box, select where the document is placed.
(A): Source