I try to run the Sonar X3 producer trial, and when it loads Fxpansion's Guru vst plugin, I'm continually prompted for the serial number of Guru.  Guru is already authorized, works in my other two hosts, and works in standalone mode.  Any workarounds or known solutions to this?  This is a show stopper for me at this point, if I can't run Guru.
 
thanks

No way to sugarcoat this, but Sonar is incapable of affecting your registration for other software.  If i had to guess I would say you probably have another guru dll  on computer and Sonar is found and unregistered copy when scanning.  Check the file path of the dll being accessed in other programs and compare to path the one being used in Sonar is using. Bottom line is any message coming promting for a serial number is completely unrelated to Sonar.

Sadly, SONAR is able to affect registration of other (VST/DX) software - it can happen when SONAR crashes (thankfully rarely).  In this case, I'd suggest that this is down to a registry permissions error, so run SONAR as administrator and try registering Guru then.

For some reason I have believed that it is always best to run Sonar with admin rights.

kakku
For some reason I have believed that it is always best to run Sonar with admin rights.

Yes sir, I have too.

Forgot about the whole admin rights thing. I kind of do that on autopilot now.

I opened Sonar with administrator rights.  The Guru authorization dialog box still opens up and won't accept the serial#.  The plugin is already authorized.  I've used it with MuLab and Samplitude.  I was also using it with Sonar 6 and Project5 (which I had uninstalled prior to installing X3).
 
I'm also in contact with Fxpansion and will update here if I learn anything interesting.
 
thanks

Did you check the file paths? I mention this because that happened to me once because I somehow had the dll from a demo version of an fxpansion app on same computer as licensed one and scanner found wrong one. Longshot but worth a try

Yes, thanks. I searched my whole drive to make sure there was only one guru.dll present.

dubdisciple
Did you check the file paths?

Yeah I'd start there. Maybe also a 32-bit/64-bit thing? I used to get those all the time. 
 
I'd tear GURU out and reinstall it. Do a reg clean in-between too. I use CCleaner but there are lots of freebz that'll scan it and pull out orphaned entries.