Can any one explain how to route this plugin? I have the MIDI data the vocal track is to follow to create the harmonies, but I can't, for the life of me, figure out how to blend the MIDI into the plugin. Antares says to place the plugin into the FX chain of the vocal track. Their presets work fine on the vocal track. I just can't figure out how to get the MIDI to control the plugin.

I hadn't tried this before, but I finally got it to work.  Insert the HE EVO in the FX bin on the vocal.  Click on the "VST2" button in the menu bar at the top of the plugin window and select "Plug-In Properties".  Check the "Configure as Synth" box. Close.  Now go to your MIDI harmony guide track and you should now be able to select the Harmony Engine as the MIDI output.  Then in HE EVO in the Harmony Control section in the upper right corner, set the "Harmony Source" to your preferred MIDI input.  I was lazy and used "OMNI" for this since I didn't have any other MIDI in this project, and just wanted to see if I could get it to work.  The MIDI Channels option might be more useful but could be a little more problematic since you can't select the channels - it looks like you have to use channels 1-4 (from the manual):
 
MIDI Channels Mode
In MIDI Channels mode, channels 1-4 of the MIDI bus assigned to Harmony Engine Evo are routed to the matching numbered harmony voice channels.
 
About Routing MIDI to Harmony Engine Evo
In order to use the MIDI Harmony Control modes described above, you must be able to route MIDI data to Harmony Engine Evo. The method of routing MIDI to a plug-in varies pretty dramatically (both in technique and ease) among various hosts. If you are unsure how to do it in your particular host, you should refer to your host’s manual for instructions. In addition, check the Read Me that accompanies Harmony Engine Evo for a guide to a few of the more obscure routing schemes
 
The downloaded installer doesn't have the ReadMe or Tutorials so I couldn't look into this further.  But that should get you going.
 
 
 

SF_GreenInsert the HE EVO in the FX bin on the vocal.  Right click on it in the FX bin and select "Properties".  Check the "Configure as Synth" box. Close.

I don't see any properties in the dropdown menu:

I had the same problem following the instructions.
1.Put the HE in the FX bin
2. open the HE
3.click VST3 in the opened HE window Which will give you the plug in properties page
4. click the plug in property page
5 Check the "Configure as Synth" box
6. click the VST3 button again and 'select enable midi input'
Then open a midi track and direct the output to the harmony engine that is now availible. I am not sure all thise steps are really needed. I did not need to do step 3-5. But I also had not been able to figure HE out to  SF_Green's response so thanks

My bad!   I edited the original post but here is the relevant bit:
 
Click on the "VST2" button in the menu bar at the top of the plugin window and select "Plug-In Properties".

Here:
 

You can also do it from the old Plug-In Manager and hit the properties button.  It brings up the same screen.  The main thing is to get HE EVO configured as a synth so it can have MIDI input routed to it.

SF_Green
You can also do it from the old Plug-In Manager and hit the properties button.  It brings up the same screen.  The main thing is to get HE EVO configured as a synth so it can have MIDI input routed to it.

Your screen capture shows you are using VST2. Do you know that there are VST3 versions available.

I contacted Anatares a few months ago and posted their reply. In it, they confess to a problem with their VST3 versions conflicting with Sonar, and recommended using the VST2 ones.
 
At any rate, I did something wrong. I finally got the thing to work, as you guys have shown me. However, the harmony output was horrible. It appears that the HE plugin is taking input from ALL the MIDI tracks in the song, not just the one with the chords. But in an effort to delete the tracks, I lost the plugin altogether. When I fired up Sonar again, I got a "can't find Harmony Engine EVO, etc." It disappeared from the plugins list. A rescan failed to resurrect it from the binary graveyard.
 
My old TC-Helicon Voice Prism Plus is looking better and better. This whole software-based synthesis is just too unreliable, at least on a Windoze machine.

Hi mudgel, yes I did, but I've never gotten it to even show up in my VST3 list  (when showing "All Plug-ins").  Maybe this is the 'conflict' that Antares fessed up to Ricebug about.  Know any tricks to make that happen?