I typed in Addictive Drums 2.dll, and still it says there are no results.  I emailed XLN Audio, and they said to delete all my Addictive Drums 2.dll files.   I told them there are none, and they have not replied.   I guess it has them baffled too.   
I don't know why Sonar X3 it says Addictive Drums 2 is there (but only 32-bit), but there is no .dll file for it on my computer.
 
Greg

I guess what I'd do in this situation is uninstall AD2 altogether, then start fresh with a new installation, paying attention to the drive paths in the Advanced tab during the new install.
 
Or just wait for XLN Audio to get back to you if you're patient enough! But it certainly seems like something's goofed up and they may end up recommending a fresh install anyway.  Keep us posted on how things work out!

I was going to uninstall it, but when I type in " uninstall," Addictive Drums doesn't even show up.....even though when I go to "insert" in Sonar, it shows it being 32-bit.   Odd...
Thanks for all your help!    I really appreciate it!
Greg
 

It just sounds like you didn't install the 64-bit version at all. You said the Online Installer asked you to pick a "new location"? Did you? Then didn't the 64-bit plugin install there? Don't forget to add that to the folders that Sonar scans.

When given the choice, I always download the 64-bit version.   So I don't understand why the 32-bit version installed instead.    I don't recall saying the Online Installer asked for a new location (perhaps I did).  
 
I would delete everything and start over, but since I can't find the .dll file, I don't know how or what to delete.
 
Thanks!
Greg

What if I just download the 64-bit version, since I have no idea how to uninstall the 32-bit version?

So here's what I decided to do, in case anyone else has the same issues.
 
I uninstalled the XLN online installer.   But when I did, it asked me what items I wanted to uninstall, and I chose Addictive Drums 2.   And it uninstalled the 32-bit version.   Then I re-installed Addictive Drums 2 and clicked on Advanced Tab, choosing 64-bit (it was going to install it in the same path it was installed previously).
After clicking on 64-bit pit and choosing the correct path, I installed it.   
 
After it was done, I searched for "Addictive Drums 2.dll," and again, there were no results.   So I went into Sonar X3 and clicked on Insert, and instead of seeing Addictive Drums 2 (32-bit), as was the case before, it just said, Addictive Drums 2.   
So it's installed.
 
Greg