Select the file you want to copy to the USB flash drive by clicking on it once. If there are several files that you wish to copy to the USB flash drive, press and hold the Ctrl key while you click on each file. The files must be in the same folder for this to work. Otherwise, you will need to copy them to the USB flash drive one at a time.
Once the files are selected, click on any highlighted file with your mouse, hold down the mouse button and then drag the file or files into the USB flash drive folder. Once your mouse pointer is inside the USB flash drive folder, release the mouse button and the files will be copied into the folder
Another way to copy files to a USB flash drive is to skip opening the USB flash drive folder altogether and going directly to the folder that contains the file or file you want to copy to the USB flash drive. Select the file (or files) in the same manner, then right click the highlighted area, point to Send To and select the USB flash drive in the list.

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