I posted a briefer version of this in reply to a Command Centre thread, but thought it better placed as a new thread. Hope that's ok Admin.
 
So I've just built a new main machine, x64 DAW and upgraded to Platinum. The idea is that the PC has three SSD's; one for the system, another for programmes, and a third for data files etc.
I made what turns out to be the mistake of installing Platinum via the Command centre, not realising that doing this does not present the option of selecting drive locations for specific parts etc.
Being also new to Windows 8.1, I was surprised to find that, despite being installed, SONAR did not appear to have the usual options available to uninstall. So the only option I believe I had was to search for all Cakewalk files (all located in various folders within the system "C" drive, in "Program Files" or "X86Program Files" including sub folders "common" etc.) and delete them.
 
So this I did, and I am sure I've located all Cakewalk files and deleted them.
 
I have then downloaded all installation files from the Cakewalk site via my account, but when I go to install, a window advises me that it has detected that SONAR either is, or has previously been installed on the machine, and that the Shared Paths destination has already been determined. Whilst I can amend the locations for various files including VST's etc. to an alternative drive to "C", the location for shared files appears in the window, but is "greyed out" and dictating that it shall go to my C drive, in Cakewalk subfolder that I have deleted (presumably it shall create the sub-folder it needs).
 
Still with me?
 
So, is it mandatory that some files must go onto the System drive, or is it just because SONAR knows where they were previously and they can function, be accessed from any location (should I have started from scratch with a custom installation)?

Is this a registry thing? Can I relocate them afterwards? I appreciate it's not the end of the world, but I'd like to ideally have things in certain locations, and keep my system drive exclusive for mandatory system running only, if possible.
 
Any suggestion on how I resolve this please?

Hi Ginger, the problem stems from the fact that you deleted rather than uninstalled, this leaves all the registry entries intact, consequently when you go to reinstall the installer finds the registry entries and thinks that SONAR is still installed.
 
You could either manually edit the registry and remove the cakewalk entry or use a registry cleaner.  The cleaner may not work either as the registry may be a tad confused. 
 
Remember to backup the registry before editing.

OK thanks Wookie.
What if install. Then unistall using command centre?
I wonder if that'll work. If so it may be safer.
Will give it a go maybe.

click the settings icon in ccc to specify paths...

GingerTomMusic
OK thanks Wookie.
What if install. Then unistall using command centre?
I wonder if that'll work. If so it may be safer.
Will give it a go maybe.

That would be a plan as noted you can set some stuff from the gear wheel in the command centre

Uninstall, or install then uninstall didn't solve the problem, regardless of the installation being via CCC or from download files. CCC setting permit you to specify paths for downloads and VST's, but shared files.
Ran CC Cleaner affter yet another uninstall. It detected many unused dll files and removed them from the registry, but when I installed again, I still got the "Cakewalk detected..." message, and any installation resulted in the main programme and VST's being installed on my nominated drive, but things like Shared DXI and Cakewalk Content going onto my C drive. Very frustrating.
I'm not skilled enough to go poking about and manually doing stuff with the registry.
 
I guess I could reinstall Windows. I would lose little other than need to reload a few drivers. All other stuff is stored on the other drives, or on my back up server, or both, so impact would be minimal. Just an hour or two of time.
 
However, before I do this, does anyone know if things like shared dxi files etc. actually need to be on the system C drive? They are obviously not necessarily exclusive to Cakewalk. Are they bit like shared documents, and therefore remaining on the C system drive is mandatory?

There is an 'uninstall' option (right click Sonar in C3). It is in the doc's somewhere as I recall. I pretty much went through the same thing. You might try a re-install from C3 and then a un-install to clean system stuff up, and install once again. Don't forget to re-scan your VSTs.
 
It didn't change my shared paths and there doesn't really appear to be an option (I have old DP,Rap, etc) that use that registry link.

I found the uninstall option in CCC too late for the first issue, but have since used it in my efforts to fully resolve the problem (?) I'm trying to solve. 
The rule seems to be that if you install from CCC (C3), you only have the option to uninstall from the same platform.
If you install from down loaded files (in the old manner), then you can uninstall either via C3, or the normal windows "uninstall a program). Doing both has not resolved the issue that any subsequent installation still detects an old one, and therefore where previous Shared Files will be installed. If I had installed from downloaded files in the first instance, I would have been able to nominate an alternative location. That option is now not available, nor does it appear, is ever available if C3 is used. There must be something hidden away somewhere that is forcing this mandatory placement, but I guess only Cakewalk know, and as it's hidden, I suspect there's a good reason for it.
I'm going to make a decision today as to if I install Windows clean, and then Sonar from scratch. I suspect that will solve things, although I wonder if it's worth the trouble. It's just my OCD playing havoc I think.
Things should be easier than this. Thanks all for your comments.

Sonar and any plugins should be on you C:/ drive along with your operating system and other programs.

Samples , loops and other content should be on another drive. If you have a third drive use that for your Sonar projects and other created content. If you only have 2 drives then samples and projects and the main drive as outlined in the first paragraph.

The shared files have a default location usually in C:/Program Files/ Cakewalk/

This is so that you can have multiple Sonar installations like I have X1, X2, X3, and Platinum all installed but they share files in the Cakewalk Folder tree.

I have a 256GIG SSD and have barely used half of it and I have 900 + plugins run, MS office the full Adobe CS5.5 Master Suite and all the Sony audio and video software not to mention scores of other utilities connected with audio and video work. Studio One V2 Pro, Pro tools 9HD, reaper, Notion and the list goes on.