guide below
How to add portal to mag250/254/256
How to add/change a portal:
The easiest way is to start from the beginning.
1: turn off your box and then turn it back on.
2: when you get to the "Loading" image, press your "set/setup" button on your remote. This will bring you to the "inner portal".
3: press your "set/setup" button again. Then go to "Servers".
4: change "portal URL 1" to the new portal by pressing the "KB" button and typing the address
http://
5: press the "KB" button again and press ok, then you will be returned to the previous screen.