To Use the Drag-and-Drop Operation to Select Files from Windows Explorer

From the Initial Model list box in the Batch Process dialog, choose the models to process in each file: All Models, or Default Model Only.
Note: After you select the files and directories to process, you can modify the Model setting for any of the files.
Open Windows Explorer and navigate to the directory containing the files to be processed.
Do one of the following:

In Windows Explorer, select the file that you want to process.

or
Press and hold down the <Ctrl> key, then select multiple files.
Drag the selected files to the Process Tasks list in the Batch Process dialog, releasing the <Ctrl> key to complete the task.
If you want the files to be dropped between two existing tasks, position the pointer between them prior to dropping the files.