I experienced a problem where about a dozen .wav files for preset sounds had been replaced by .sfz files during my initial install of Sonar X2 a couple of weeks ago. Called Cakewalk support who sent me instructions on uninstalling Rapture (along with the necessary deletions in my registry). I then re-installed Rapture only. While this has corrected the error messages and appears to configure itself for the sound selected, I am not getting any output from the Synth. The track screen meters show no received data at all. I have tested other Synths and find all are working properly. This condition is consistent with the use of a Keyboard (A300) and by using the virtual keys on the piano screen. Any ideas on what may be causing this?
 
Brian

Launch Sonar as administrator and register rapture? That's the first step. Have you registered it?
 
To Register it, launch sonar as administrator, open a new project and insert a Rapture Soft Synth. At that point you should be prompted to enter the product key.
 
http://www.store.cakewalk.com/b2cus/login.aspx
Login to Cakewalk Store account here to find your Rapture Product Key.

Problem has been corrected. I, once again, uninstalled Rapture. This time I did a little searching and found one remaining file in the original Rapture directory. I believe that this was some form of a settings file. Deleted that directory and reloaded Rapture. All is normal now.

FABULOUS news!  Good luck enjoying all the goodness.
 
Bob Bone