On our experience to reflash a box, you cannot do it thru a Wifi Dongle or connection (Only the hardwired one Vonets would be OK, as in fact it's just a RJ45 cable for the box), you will need then to connect your box to the Router/Modem to flash it.

But often the recent images are upgradable thru internet, via the feed servers. If you want to keep your image and just upgrade it, then just do it online. But for reflashing, you will need a Router/Modem and real RJ45 cable.

There is in some boxes the option to use the Service Port (Mini-USB port), with the proper software (DreamUp/JapharFlasher), but this is not available for the DM520HD/DM525HD, and DM900UHD/DM920UHD, as well as the new DreamOne/Two/Seven until today.

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