Hi, I am trying Sonar Professional before upgrading. I used to load Sforzando Plogue as a VST instrument in Sonar X3, but Sonar Professional only let me use Sforzando Plogue as a VST FX on an audio track and I can't link a midi track to the audio track because there's no VST instrument. Is there someone who knows what I am doing wrong? Is it related to the fact that I am using the trial version of the product? Thanks for your help

Not sure - I just tried v 1.669 of sforzando in SONAR Platinum here and works fine (From Insert/Soft Synth) - I selected "Simple Instrument Track" from the insert options menu - 
If you check the Plug in Properties for Sforzando does it show up as a VSTi or a VST? (Utilities/Cakewalk Plug-in Manager) - if it shows up as a VST effect, you should be able to tick on the "Configure as synth" box to set it up as a VSTi).
I doubt that anything with SONAR Professional would have changed that though.....

Run a VST reset from SONAR Preferences > File > VST Settings. The plug-in should scan as a synth.

Ok I ticked the "configure as synth" box in the plug-in manager properties and Sforzando is show in the uncategorized vsti but instead of being green or blue the icon is grayed. It seems Sonar doesn't want it there for some reason. It's Sforzando version 1.1916. I also tried the reset vst option but still the same result. Now Sforzando is not seen as VSTI and is not seen in audio fx either.

Does it still load correctly in X3?

Yes it does

Is there a chance X3 is 32bit and Professional is 64bit? If so, try installing the 64bit version of the plug-in.

I think I found what I did wrong, it might be a registry entry l should not have deleted while trying to make things clean. I reinstalled a previous windows image and installed Sonar Professional and Sforzando is back on track. Thanks anyway!