Weird Issue with VSTi (Plugin manager)

I have an unusual issue with a particular VSTi plugin.  I have had the issue with both X2 and with my very new X3 upgrade:
 
Last week, I got Sonivox Eighty-Eight 2.0  I installed it and activated it.

Since then, I have been unable to load the VSTi in Sonar.  (First with X2 and Now with X3).     I have it in a place where it is scanned by my plugin manager. 
 
When I go into a project and select Insert a soft synth, it is not listed.

The strange thing, however, when I go to Plugin Manager, and look at the master list of my VSTi Sytns, it is listed. 
 
A couple things - My initial scan of the Synth was done before it was activated. (I have scanned it since activation) I am not sure if this is an issue.

Second,  the Plugin Manager seems to take longer while it's scanning the particular dll file for this Instrument.

Any suggestions would be greatly appreciated. 

By the way, I am really enjoying X3.

scook
When looking in the Plug-in Manager, is the "Show Excluded" option set? When performing the rescan, did you use the reset button in Preferences > File > VST Settings?

I should have mentioned in my original post - The plugin in question is not on my excluded list.
 
Thanks.

scook
Are you using the "Default All Plug-ins" layout?

Yes, I am using the Default plug-in layout.   Should I not be?  

I doubt it would make a difference but if you are not running SONAR as administrator, you could try it.
 
edit: yea for some reason, I have supervisor on the brain fortunately someone is quite to correct me although I doubt it would matter either way

In the Plugin  Manager, you say it is in the master plug in list, but does it also show in the list to the right that displays the plugins in the default layout?

Just a guess but did you install that vst to the default folder?
I usually install everything to C:/Program Files/Cakewalk/Vstplugins but I have had a couple vst's that would only work if installed to the default.

Yes, that would be the problem if one is not using the "Default All Plug-ins" layout. I asked  previously about the plug-in layout. SONAR by default displays all plug-ins; the layout is built on the fly and cannot be edited. On the other hand using any other layout requires plug-ins be manually added to the layout using the Plug-in manager layout editor (the right side of the Plug-in manager).

You may need to try a reset/rescan.
 

I appreciate all your suggestions.

One thing I am wondering - if it has anything to do with the plugin being properly authorized.  I did an online authorization and I got the message (on the Sonivox website) that the plug was "authorized."  I wonder if there was an issue authorizing it on my computer.  The reason I wonder, I took advantage of the freebie from the People at Addictive drums.  It was the Peavey ReVaulve VST Plug in and  I scanned it before authorizing it.   When I tried loading it, it was not visible.  After authorizing it, I did see it
in my list.  Maybe there's something similar going on.  I will investigate this angle and check with Sonivox support next week..

Thanks again for all the suggestions!