[Update] - The shoe maker's elves must be dabbling in DAWs because everything seems to be working just fine now. No magic steps required before opening and running a project. No crashes or VST Scan hangs. The two changes on this system:
1. Installed 2016.12 Sonar update (since rolling back to previous versions or anything else did not solve the problem.)
2. Updated Win10 (Pro) OS Build  to 10586.713
- Note: I have -not- installed the latest versions noted in the Early Access sticky on CA2A and Z3TA+2. It's running fine with the previous versions which appears to be the case for most users. 
 
(executive summary to save reading all the comments)
[Original problem] - Several CW VSTs would crash a project on load or on insertion into an FX bin. VST Scan would hang when trying to scan the problem VSTs. VST functionality could be restored by deleting all keys in the registry and reinstalling them but this approach only worked as long as the PC was not restarted. Once the PC was restarted, the problem reappeared. 
- Note: Rolling back to a previous version of Sonar did -not- solve the problem and per other users a System Restore did not solve the problem. 
- Note: No issue noted with any other VSTs. 
 
[Root cause] - The most useful comments came from the CW Dev team and attributed it to a "timing issue" with a few CW VSTs which was exposed after a Win10 update in Nov.
 
[Workaround] - Run the MS Procmon tool before loading a project or inserting one of the problem VSTs as this apparntely adding a slight delay to the problem threads to keep them running. Other users noted that only a Sonar Start/Close and Start again was sufficient to load and run a project -on their systems-. 
 
[Solution ?] - CW dev team seems to have a good understanding of the issue and per the latest sticky we are expecting updated versions of the problem VSTs. 
 
 
....
 
 
Because I use it on just about every project. The original PC version has been in use for quite some time, was updated via the latest version in CCC when released. Has been fine until today. Only action was to install the 2016.11 update. The issue appears to be with a core Cakewalk setting as the Cakewalk VST Scan seems to be stumbling on other Cakewalk VSTs.
 
> Installed 2016.11 update
- let CCC install to default locations
- including the two FX updates

> Was able to work on the current project at the time
> Closed Sonar, powered down PC
> Reopened project = Crash "SONARPLT.exe has stopped working"
 
> Opened another project in Safe Mode
- The current project was fairly large, tried a smaller one.
- CA2A will crash it every time. All else seems to be OK
 
> Reset / Rescanned VST plugins (via Preferences | VST Settings)
Thought maybe the FX updates had something to do with it.
 
- VST Scan throwing "Runtime Error!" dialogs when scanning
     - LP-64_Multiband_64
     - LP-64_EQ_64
- VST Scan crashes "Cakewalk VST Scan has stopped working" when scanning
     - CA2A Leveling Amplifier
 
> Rolled back to 2016.10
- SAME issues !!?? Had been working just fine. Probably not the update, but what?
 
> Reinstalled Sonar Pt 2016.11, CA2A, Engineering FX via CCC
 
> Reset, Rescanned
   . Rescan Failed Plug-ins = checked
   . Rescan Existing Plug-ins = checked
- The VST scan seemed to be "struggling" to get thru the inventory. By this I mean it would display a dll and appear to get stuck instead of zipping through them.

> Unchecked "Rescan Existing Plug-ins", rescanned
- Noting the scan would still appear to hang on various Cakewalk dlls (i.e Rapture Session, RMix, Z3ta+2, etc.) 
   . I would close the scan status window and hit Scan again
   . It would eventually appear to complete the scan, noting "7 new" plugins
 
> Tried opening the small project.
Crash. Safe mode still shows CA2A to be the culprit
 
> Deleted aud.ini. rebooted, tried opening the small project.
Crash. Safe mode still shows CA2A to be the culprit
 
> Deleted CA2A in the MS Control Panel | Programs & Features
Eliminated both the original install and the latest update.

> Reinstalled CA2A via CCC
 
> Tried opening the small project again.
Crash. Safe mode still shows CA2A to be the culprit
 
> Tried another Reset/Rescan
- Opened a project in Safe Mode without loading CA2A. All working.
- Added an instance of CA2A to the PC of a track. All working.
- Saved and closed project.
- Tried to reopen the same project.
Crash.

.....
I have to think some core setting/dir must be corrupted. It's not like these are dodgy 3rd party plug-ins. The only action other than running Sonar as usual was the 2016.11 update and that worked for at least one session.
 
Any expert insight would be appreciated. In the meantime I'll be digging deeper.  
 
[dedicated project DAW]
Win10 x64, latest updates, Asus X99A, i7-5820, 32MB, Radeon HD 5450, Roland QC4
 
 

I can confirm the same problem. CA2A crashes my projects every time since latest update.

im sorry to hear about this. I know the frustration when you cant complete tasks such as opening a project.
Anyway, I loaded up CA2A in a few FX bins here (Im on windows 8.1 X64 / Sonar X64) and it works fine here.
I also decided to give the Pro Channel Module CA2A plug in a try and same there, all good.
 
So we get to the point, Are you all up date on your Windows updates ?
There might be a C++ update that needs to be done. typically those are the important ones.
You can also try and re personalize by holding down CTRL+Start Sonar.

Thanks Chuck! What exactly does Ctrl + Start Sonar do? Also, I looked for the aud.ini file since deleting it and letting Sonat recreate it used to be a fix in the past but I can't locate it anywhere on my computer. Is that file no longer used?

Chuck, also just noticed you're on Windows 8.1 and I'm on 10.. Maybe that's the difference?

As noted in the original post, showing the latest updates installed for Win10 x64.
 
Not sure how to confirm the latest C++ update, will look into that. 
Control Panel | Programs and Features shows
- "MS Visual C++ 2015 Redistributable (x86) - 14.0.23026"
- "MS Visual C++ 2015 Redistributable )x64) - 14.0.23918"
 
....
Created a brand new project using the basic template.
Tried inserting CA2A into a ProChannel on an Audio track
 
Crash. 
 
Seems to be a core issue, given that Cakewalk VST Scan seems to "struggle" with other Cakewalk VSTs.
 
Rollback to the previous release did NOT fix it. I'm back on the latest update (2016.11). 
Writing this up for the Problem Reporter, and then more cause & effect, registry diving...

@dlesaux
 
Aud.ini is located in the following directory.
C: / Users / <your user name for the PC> / App Data (hidden directory) / Roaming / Cakewalk / SONAR Platinum 
 
Please note I tried deleting this per my original post to force Sonar to rebuild it.
 
It did not solve the problem. 

The first time I tested this, SONAR crashed after simply dragging CA-2A into an FX bin. However, I was unable to duplicate it on several subsequent attempts.
 
Faulting application name: SONARPLT.EXE, version: 22.11.0.111, time stamp: 0x583d02e6
Faulting module name: CA-2ALevelingAmplifier_64.vst3, version: 2.0.1.97, time stamp: 0x5802558a
Exception code: 0xc0000409
Fault offset: 0x0000000000085e88
Faulting process id: 0x1118
Faulting application start time: 0x01d24ca35a102aea
Faulting application path: C:\Program Files\Cakewalk\SONAR Platinum\SONARPLT.EXE
Faulting module path: c:\program files\common files\vst3\CA2ALevelingAmplifier\CA-2ALevelingAmplifier_64.vst3

jackson white
@dlesaux
 
Aud.ini is located in the following directory.
C: / Users / <your user name for the PC> / App Data (hidden directory) / Roaming / Cakewalk / SONAR Platinum 
 
Please note I tried deleting this per my original post to force Sonar to rebuild it.
 
It did not solve the problem. 

Thanks Jackson! Please keep us posted on any response from the bakers. I'm sure we're not the only ones having this issue. Based on Chuck's feedback, it also seems to be related to Windows 10 users.
 

bitflipper
The first time I tested this, SONAR crashed after simply dragging CA-2A into an FX bin. However, I was unable to duplicate it on several subsequent attempts.
 
Faulting application name: SONARPLT.EXE, version: 22.11.0.111, time stamp: 0x583d02e6
Faulting module name: CA-2ALevelingAmplifier_64.vst3, version: 2.0.1.97, time stamp: 0x5802558a
Exception code: 0xc0000409
Fault offset: 0x0000000000085e88
Faulting process id: 0x1118
Faulting application start time: 0x01d24ca35a102aea
Faulting application path: C:\Program Files\Cakewalk\SONAR Platinum\SONARPLT.EXE
Faulting module path: c:\program files\common files\vst3\CA2ALevelingAmplifier\CA-2ALevelingAmplifier_64.vst3
 

Thanks for trying to replicate this bitflipper!

bitflipper
The first time I tested this, SONAR crashed after simply dragging CA-2A into an FX bin. However, I was unable to duplicate it on several subsequent attempts.
 

exactly the same thing here: immediate crash on first insert. not producible at following inserts!
 
EDIT: after reboot - same problem in same project. so reproducible it is!