How do I transfer Sample Libraries and Project Files to a new Drive?

Make a folder on the new drive named Installed Samples or someting, just re-install the softsynth/sampler and when the installer asks you where you want to install the sample content, browse to the folder you made for samples on the new drive.

For Cakewalk Projects, just copy the entire Cakewalk Projects folder to the new drive (D:\), and in SONAR Preferences under File>Folder Locations>Project Files, change the loaction to D:\Cakewalk Projects.

Under Wave Files (note the file path), copy that folder of the old location to the new location of D:\ and in SONAR Preferences under Wave Files,browse to the new location on the D:\ drive.

And under File>Audio Data (note the file path) copy that folder to the new D drive inside the Cakewalk Projects folder on the D drive, in SONAR Preferences, change the Audio Data location to D:\Cakewalk Projects\Audio Data or whatever new location you copied the Audio Data folder to. (The default audio data location is a folder in the Cakewalk Projects folder called Audio Data.)