Tried updating to the latest Newburyport version of Platinum through the CCC.  At the very end of the install it gave me a screen saying:
 
C:\program files\cakewalk\shared utilities\cw120 auto.dll
unalbe to register the dll/OCX: RegSvr32  Failed ext code 0x3
 
It recommended abort the install, which I did, I then tried again with the same results.  Then I noticed my Platinum desktop icon was missing.  So I went into the program list to drag it back out.  Only now it's gone from the program list as well.  Not to be found anywhere.  In short, NO SONAR!!
 
Any help will be greatly appreciated.

Try downloading through your Cakewalk Store account?

See http://forum.cakewalk.com/FindPost/3393632

Luckily just downloading and installing directly from my account fixed it...I think. Just to be safe I also downloaded the c+++ files. Thanks to all!

FWIW the problem and solution is the fourth item down on the SONAR support page. 

I keep all my install downloaded SONAR files to have when needed...nice job guys. -S