can you use audacity 2.0.3 with native instruments komplete 8 ultimate virtual instruments with windows 7
No, Audacity doesn’t support VST instruments and real-time effects.
However depending what you are doing you can run Komplete 8 standalone and possibly record its output into Audacity or run the VST plug-in in a free VST host like http://www.hermannseib.com/english/vsthost.htm and have Audacity record the host’s output.
Gale