I've just done a system restore of raspbmc, using a noobs SD card. I am using the same wifi dongle from this kit http://www.amazon.it/gp/product/B00LTY1 ... ge_o00_s00 I was using before.
However, now it gets not installed. It's not branded so I don't know if it's in the supported list.
On the forum I did not find any useful solution. What should I do?