This has been a small problem for a long time, but I'm sure someone can help me get to the bottom of it.  
 
I have installed quite a few free plugins, and I've found that some of the 32-bit products won't load.  They produce a large number of "Can't load module....." errors in bitBridge dialog boxes.  I have to clear each of them before I can regain access to SONAR.  
 
At one point it looked as if all of these plugs had been authored with SynthEdit.  Does that offer any insight?  
 
I know other forum members have suggested that jBridge is a more reliable solution for running 32-bit plugs in a 64-bit system, so I downloaded that, but with no influence on the results.

Have you tried running SONAR as administrator?

I hadn't tried that before, but with your recommendation, I did.  And it worked!  Does this mean I'll need to Run as Administrator each time I might want to use problematic plugs?  Or was there something about this that actually fixed the problem?

 
By the way, you and the other heroes on this forum are awesome!  I seriously doubt there's another software forum with such knowledgeable and fast acting resources!
 
Rick

You are welcome. Chances are you will need to run as administrator any time these plug-ins are used in a project. It should be pretty easy to test. I would recommend considering replacement plug-ins for them.

I had the same problem.
I use alot a free VSTs, too. The manual had the following suggestion to fix that problem. Workes for me every time, I encouter this problem and even if Sonar is not in Admin-Mode, it should work fine ;-)
 
Note: In case of problems please read the following. Upon starting the plug-in for the first time a number of files are automatically extracted to your VST folder. On Windows versions from VISTA onwards by default plug-ins are not allowed to write files to your hard drive. This will typically cause an error message from your DAW reporting missing files. You can fix this issue by changing the write permissions for your VST folder as follows:
• Use Windows Explorer to browse to your VST Plugins folder.
• Right-click the folder – 'Properties' • Choose 'Security' tab.
• Click 'Edit' button (You may need to click a UAC prompt).
• Select user name "Users".
• Tick options Allow 'Write' and 'Modify'.
• To finish Select 'OK' to close the two dialog boxes.