Upgraded to latest Platinum. A track i am working on already has melodyned vocals on and work perfectly. i recorded a brass instrument (eb horn) and attempted to melodyne it. But all i get is a single line with no notes in it. i am using melodyne 4 essentials. Algorithm is set to 'melodic'.

If I copy the brass part and insert it into a new project, melodyne it, it works perfectly. Question is why can Melodyne not work in my main project? Any help appreciated

I assume you mean you get the single line with no notes after rendering, yes? Remember that rendering isn't just rendering Melodyne, but any other clip attributes. So what you experience will happen if a clip is muted, whether on purpose or buried in a Take Lane. Rather than chasing down what the issue is, you can just ctrl+drag the clip to a new track, apply Melodyne, then move it back to the original track.
 
Also make sure you download the latest update to Melodyne 4, one was issued shortly after it appeared.

You are a genius Craig! Yes, I had some tracks solo'd - as soon as I un solo-ed everything it worked perfectly! What a great forum this is! And I love Sonar too.

Big Thanks :)

Keano66
You are a genius Craig!

Well I'll take that , but the reality is that I've logged so many hours on SONAR I think I've made almost every pilot error mistake possible. I'm a living database of how to do things wrong with SONAR! The good news is that a lot of "Friday's Tip of the Week" come from doing something "wrong" but then finding out it does something else that's cool