I recently took delivery on a new i7 8700Kfrom Jim Roseberry   (my third build from Jim).  At the same time I went with a UAD 8P.
I have a UAD2PCIe quad card and now a new quad in the 8P. I have quite a few UAD VST's. 
However, now when PLAT starts, it scans my VST's. It gets stuck on the UAD stuff every time.  It has yet to complete a single scan of VST's.  The problem then is that many are missing.... My Reverberator plug which I love.... installed but not seen by PLAT.
 
Any ideas?

Probably you need kind a workaround. Sonar VST manager/scan has some nasty bugs.  You could create dedicated directory for UAD plugins where they were moved. The directory excluded from VST scan. Rescan all VST directories except UAD VST directory (so it cannot be subdir already included). Next you could try add to VST path your UAD VST dir and rescan again. Also you could selectively hide UAD plugin on which your scan is hanging.

Probably a stupid question - have double checked that the UAD is properly connected/configured?
Is there anyway that you can confirm (using Savihost or other VST host) that the UAD VSTs are working?
 

Looks like help is coming, Steve

stevee9c6
... It gets stuck on the UAD stuff every time.  It has yet to complete a single scan of VST's.  ...
 
Any ideas?

Has a similar issue once, not with UAD, and got past it by running Sonar as Administrator.

Which plug does it get stuck on?  For each one, cancel out of the scan and move the vst out of the vst folder and onto your desktop.  Do this until you get a finished scan.  Then list the failed plugs here for further  analysis.

When the vst scan hangs it will show the plugin it's trying to scan.
Go into the UAD vst folders and remove the offending .dll file. I had to remove chandler and a few others which are not any of the ones I use. After removing the problem .dll file the vst scan will complete with no issues.
The latest versions of uad have fixed some of these issues but it may vary from system to system.
 

typical file locations are of course c:\program files\cakewalk\vstplugins
also c:\program files\steinberg\vstplugins
c:\program files (x86)\steinberg\vstplugins
C:\Program Files\Universal Audio\Powered Plugins\UAD-2 Powered Plugins
UAD software is a bit odd the way it creates plugin folders in multiple locations but I just leave them where they are and occasionally remove one of the .dll files when it does this vst scan hang thing -

Make sure there's not some kind of splash screen hidden behind something else...check the taskbar. 

Steve, you got the big gun in here now with Craig responding.