Then I opened MIDI Settings in FL Studio and I enabled the generic controller. I fixed this when I figured out that the MPD wasn't recognized by my PC, so I inserted the USB cable in another USB slot and it was finally recognized. Also I was searching on the net to find someone with similar problem as mine, but I had no luck. I choosed FL Studio preset on the MPD26, opened FPC, and nothing happened when I hit the pads.I've installed the software that came with it but I didn't touch nothing there.
I've bought an Akai MPD26 few hours ago and since then I'm trying to configure it with FL Studio 9.