Belkin N300 wifi laptop problem

Hi, I have bought the N300 Belkin wifi range extender with the hope of wifi reaching the top of my house however have encountered some problems. I have set up the model as described in the box and also the manual, however after finishing, the wifi doesn't seem to be any different from before even though the extender is feet away from my laptop. I'm really confused why it wont work, it seemed to momentarily boost the signal but then its down to 2 bars, as it is normally without the extender.

Help would be appreciated, I am really struglling with it.