Hello
Please download the image from below link and extract the image on USB.
Windows Embedded Standard Image
Note: Above said activity need to be performed on any laptop or desktop.
Kindly follow the below instructions to create the USB bootable media.
Step 1: Insert the USB pen drive in any desktop or laptop ( For creating the USB bootable media)
Step 1 : Download the file to any location in the computer.
Step 2: Right click the downloaded file and select “ Run as Administrator “ to execute that file instead of just double clicking on that file.
Step 3: when the file is executed you can see a box with 4 options, please select USB format from those options ( Ensure that a USB pen drive is connected to the computer)
Step 4: Once the USB bootable media is created successfully, the name of the USB media will be changed to “ Thin state”.
Step 4: Remove the Pen drive and boot the thin client using that USB pen drive and follow the instruction
Once the Image is extracted on USB, you may use this USB to reimage the unit.
I hope that answers your question. 
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