The default VST path settings for Sonar on a 64-bit system are:
C:\Program Files\Cakewalk\Vstplugins
and
C:\Program Files (x86)\Cakewalk\Vstplugins
Please note that you do not need to change any Registry values to move your plugins to the above folders.
You simply have to alter the VST Scan Paths in Preferences>File>VST Settings, and then re-scan everything.
Bob Bone