I noticed lately that I can't find some of the plug-ins in Platinum that I've installed. So I started to make a little bit of investigating.
 
This is my VST setup in X3:

 
This is the setup from Platinum:

 
Seems pretty identical to me except platinum has added the folder for cakewalk sound center. My X3 finds 513 plug-ins and Platinum 487 plug-ins. The plug-ins I can't find are Flux BitterSweet and Voxengo Span and I have no idea what the rest missing plug-ins are. Both are freeware. What is going on? 

Are X3 and Splat both installed as 64-bit?

Have you Reset AND Rescanned in Platinum?

ChristopherM
Are X3 and Splat both installed as 64-bit?

Both are 64bit.
 

Bristol_Jonesey
Have you Reset AND Rescanned in Platinum?

The Rescan didn't help so I tried the Reset and the VST scanner got stuck on Waves doubler. Left it there and headed out for lunch and when I came back it was still trying to scan.
 
I'm rolling back to lexington as soon as I find out how to do it. This was my first update after upgrading and I have to say I'm a bit disappointed. I've found two major bugs already. :/ Would be really helpful to have some kind of "known bugs" thread that compiles the stuff that has already been reported.

Okay so I rolled back to Lexington and did a reset on VSTs. It seems that the VST Scan STILL gets stuck on Doubler and I can't access almost any of my favorite plugs. How can I skip that plugin and get the rest of the stuff working again? Losing valuable time. 
 
EDIT: After couple of reboots and resets/rescans the plug-ins are now fine in Lexington. Will be waiting for the next patch/fix before trying Manchester again. 

I've also found SPLAT to be a little more sensitive to VST scans than X3 (Arturia V collection gave me grief for example).  Not sure why, but I had to review/reset the VST scan paths and pay particular attention to ensuring 32-but versions were not included.  I got the sense it was taking the 32-bit version over 64-bit and then not showing the 32-bit version.  Odd.  By the time I got it working I hadn't noted down the exact recipe.
 
The one problem I have with the SPLAT agile update approach is that before, the patches addressed existing bugs but didn't add too many new features.  In the new model each release may well address bugs, but they also introduce new stuff which now carries new bug potential.  So we don't really ever get to that 'stable' environment that we had with the 'c' or 'd' releases of yesteryear.

For whatever the worth, I have nearly 800 plugins that all show up in both X3 and Platinum, however I must note that I have deliberately chosen NOT to include any 32-bit third-party plugins whatsoever in my 64-bit Sonar install.
 
I DO maintain a 32-bit version of both X3 and Platinum, but rarely use those.  They exist only for old projects that require a 32-bit plugin.
 
In addition, I have the Arturia V Collection, and using just the 64-bit version of those plugins, I have no issues.
 
Bob Bone

There was a similar problem after Jamaica (there is a previous thread). Often if you have already been working on a project in  Sonar and then do a reset and scan, your machine can run out of virtual memory and the scan hangs. Funny thing is Waves plugs always seem to be the culprit perhaps because there are often both VST2 and VST 3 versions. The best thing to resolve it is to set the preference to "scan at start up" then reboot and run Sonar. You can then change the preference back if you want. As to the missing plugs, it could be the preference to ignore 32 bit versions if a 64 bit version is present is set differently on X3 and SPlat. On mine Voxengo plugs go into a Voxengo sub folder. I have around 900 plug ins (who knows why?) and have no issues.