If you are having difficulty reading a USB Drive plugged in to the touchscreen on either a SUMMIT or a Bernina E16 PRO, this article should help troubleshoot the situation.
Make sure your SUMMIT or Bernina E16 PRO is running the latest version of the UI App, which is identified in the Maintenance Screen.
There is a test function for the USB ports, which can be found by navigating to the Maintenance page from the main screen, and then to the 'Hardware Test' page. On the hardware test page there are icons for the five physical buttons on the touchscreen as well as the internal speaker, the barcode reader, and the two USB ports. The icons for the buttons or USB ports should show when any of the buttons are activated or when any USB thumb drive is plugged into one of the USB ports.
SUMMIT and Bernina E16 PRO are both compatible low-capacity and high-capacity USB drives which have been formatted to either FAT32 or exFAT format.
If the other functions on the hardware test page are working but the USB icons do not light up when a drive is inserted (and the drive is properly formatted and works on other machines), there may be a hardware problem with the USB ports. If NONE of the peripheral functions are working, then there may be a hardware problem with the USB controller inside of the touchscreen (the physical buttons and barcode scanner use the same USB controller as the external ports). Either of those issues would require replacing the touchscreen.