"3. Insert the USB memory device in the receiver USB port.
4. Power ON the box and repeatedly press and release the MENU button on the remote to invoke the boot
loader for downloading the S/W image via USB."
Hope this helps.
And if you want to read the whole PDF file, then go to www.dishtv.co.nz, select aerial box in the menu and you'll find the T1020. Then all you have to do is scroll down the page to the links.