My Novation keyboard works fine with Z3TA, Dim Pro and other synths. Suddenly Alicia Keys within Kontakt Player 5.1 doesn't work. It receives midi allright but just doesn't transfer it to the piano. When I click the mouse on the keyboard in the Natives window it does sound allright. Is there a solution?

Do you have the Channel within Kontakt and Alicia Keys pointing to an appropriate MIDI input channel, like Channel 1? If you had other Kontakt instruments in there and deleted one or more your Alicia Keys might indicate its input is presently on MIDI channel 2 for example.

Thank you lawaja!
The problem was not exlusively within Sonar. When I tried Kontakt as stand-alone no Impulse midi turned up here either. Installed the obsolete drivers from the CD coming with Impulse and then it works! I have no idea why the up-to-date driver didn't work.