It is best to leave the SONAR installation on the C drive, using the D drive for projects and audio data but it is possible to free up quite a bit of space. About half of the the disk space of the install was consumed by the "Cakewalk Content" directory and the Dimension Pro multisamples. These pieces can be relocated without reinstalling.
Move the "Cakewalk Content" folder where ever you wish and update the entries in
Preferences > File > Folder Locations. This is the easiest way to get back about 25% of the space consumed by the X3 Producer install.
Move the multisamples folder for Dimension Pro. The multisamples folder for Dimension Pro is located in "C:\Program Files\Cakewalk\Dimension Pro\Multisamples" or "C:\Program Files\Cakewalk(x86)\Dimension Pro\Multisamples" (in the case of a 32bit installation) directory. After moving the folder, Dimension Pro needs to be made aware of the change. This can be done in one of two ways, either using the DOS mklink command or a registry edit.
Method 1 - the mklink command
At the cmd prompt the syntax of the command would be
mklink /j linkname actualpathFor example if the multisample directory was moved from "C:\Program Files\Cakewalk\Dimension Pro\Multisamples" to "C:\Dimension Pro\Multisamples" the command would be
mklink /j "C:\Program Files\Cakewalk\Dimension Pro\Multisamples" "C:\Dimension Pro\Multisamples"--
Method 2 - registry edit
The "Multisamples Folder" key needs the path to the Multisamples folder. For example the default 64bit location is "C:\Program Files\Cakewalk\Dimension Pro\Multisamples" the "Multisample Folder" entry would be "C:\Program Files\Cakewalk\Dimension Pro"
The "Multisamples Folder" key could be in two locations:
The 64bit location is HKEY_LOCAL_MACHINE\SOFTWARE\Cakewalk Music Software\dp
The 32bit location is HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Cakewalk Music Software\dp
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The installation footprint can be slimmed down even more by moving all the sample based content. Here is a thread detailing all the registry changes from
http://forum.cakewalk.com/FindPost/2673527. It is possible to use mklink instead of registry edits for these changes too.