I am pretty sure 32bit DXi will not show up in 64bit SONAR. They are not registered in the same location. I don't believe moving already registered DXi causes a crash, it causes an "bad installation" error message.

If reinstalling does not work, consider contacting tech support.

These are a lot of possible reasons why they don't work. If I truly needed the synths, I might take further measures. I guess it will suit me fine to leave things as they are. As I said, I haven't used the sounds, and my system is pretty stable without them.
 
Thank you, everyone, for helping.

scook
I am pretty sure 32bit DXi will not show up in 64bit SONAR. They are not registered in the same location. I don't believe moving already registered DXi causes a crash, it causes an "bad installation" error message.

No they don't but wrapped ones do. They become VST plugins to Sonar.

SONAR still supports DXi's. If its crashing its most likely a plugin install issue where somehow the plugin cannot find its resources or some such thing. DXi plugins need to be registered via regsvr32 to even show up. Normally the installer does that automatically but sometimes the registration can get messed by running registry clean tools or AV software. In that case you can try running regsvr32 pluginname.dll from an admin command prompt.
 
DX plugins do not have a bridging layer so you must have 64 bit versions if you are running the 64 bit version of SONAR.

Someone else is having problems http://forum.cakewalk.com/FindPost/3099658