The file that you want to print is not listed in the USB Flash Drive menu
You might be trying to print a file type that the USB printing feature does not support. The
product supports .PDF and .JPEG file types.
You might have too many files in a single folder on the USB storage accessory. Reduce the
number of files in the folder by moving them to subfolders.
You might be using a character set for the file name that the product does not support. In this
case, the product replaces the file names with characters from a different character set. Rename
the files using ASCII characters.