Ok, here is the skinny. I purchased Platinum back in March. I have nothing but crashing. Crash when I loop, crash when I rewind! crash when I clone tracks, crashes when opening plugins,  Crash crash crash crash crash! Crashes and I loose data, crashes and I lose time, crashes and I loose sanity! Now before you lecture me on system resourses, here is what I have;
ASUS ROG, Corei7 (3rd Gen), 16G Ram, 500G SDD & 750 HDD. . . . Plenty of horsepower.
I have read, and tweaked and checked drivers and reinstalled till the cows came home and left again! I had no problems with X2 so
in my appreciation of the product I upgraded, and well your get the picture.
Ok, here is the rub. I decided I want to relinquish my license and have requested assistance in returning (uninstalling) the product and getting a refund. I am willing to concede that my system is just somehow incompatible. I have submitted bug reports with no response, and then when I finally threw in the towel and opened my ticket. . . . . . .silence! Not a peep outside of the generated form that tells me they received my request. It has now been over a month with several inquiries all with no response.
So sad! I was such a big fan of the product but now that I have experienced the lack of support I just have lost all confidence in any future with them. Now mind you I have used Cakewalk since Guitar Studio and Producer8. Not even a courtesy response from a human to see if there might be a resolution but again, no response to any problems submitted or to this desperate action for help.
So. . . . .  not much I figure I can really do except to warn people that it is a gamble and Cakewalk will selectively decide to help I guess when it is in their best interest and not in the customers.
I will revert to X2 as a stop gap and I will save, save, save, and move onto a more supported product and tell others of my experience. No cussing, no fuming, just resolve and chalk it up to experience that integrity may exist in the world but not in this company.
 
Michael Lawrence
Nobody big, just someone who loves playing music and recording.

Based on your post count it doesn't look like you've tried to get any help from the forum. There's a lot of really smart folks here and I'm sure you could improve your situation by asking for some help. Amongst other things that will kill Sonar these are a few off the top of my head.
 
Wi-Fi adapters
Mixing 32 and 64 bit plugs
The 64 bit double precision engine
Conflicts with other audio sources like HDMI audio of a video card
Picking the incorrect driver mode. Some systems like ASIO and others don't
Win 10 drivers for your interface
 
These are a few of the things that I've seen bring down systems over the years and I'm sure there's many more. I won't excuse Cakewalk for their current support level, it's not good, but if you REALLY want to fix the problem there's lots of folks here that know far more than I do. Ask for some help and you'll get it.

Thanks John, appreciate the response.
True, I have not directly posted on any of the forums. I guess I just expected a bit more customer attentiveness from Cakewalk. If I pay for a nice stereo to go in my car and there are problems with it that weren't present with the
old stereo I would think I would take it back to the dealer/installer to make it right instead of hitting a forum and tearing into the dash to do the troubleshooting. No offence to the great folks in the forums but the first line should be the product support. Problem is, they are not responding. And though I have not directly posted to the forums, I have searched and read a lot of postings and tried many of the suggestions for similar problems.
I am running win8.1, no other attached devices or audio sources. I am running all native 64 bit plugins and have gone through the AISO/WASAPI/MME/WDM/KS driver modes(my system definitely does not play well in the sandbox with ASIO :-).
The 64 bit Double Precision Engine is unfamiliar to me unless you are talking about the "Use Multiprocessing Engine" option in the Playback and Recording Preferences to which I have tried both ways (along with just about every other option toggling). And may I reiterate, none of these issues with Producer 8 (8.5), or X2, both of which I got pretty familiar with under the hood.
But. . . . in the spirit of humility and the willingness to ask for help. . . . . . . .Help!
Not sure what other info is needed but will be happy to provide.  :-]
 

Go to the preferences section for driver settings. Beside the bit depth setting is a check box for 64 bit double precision. Make sure it's NOT selected. Some people use it and have no trouble while others have had it cause problems. I haven't used it since I had trouble with X1.
 
You won't want to use MME. If ASIO won't work then try WASAPI or WDM. I guess it would also help to know what audio interface you are using along with your video card. Sonar doesn't need a real powerful video card but recent changes with the linear phase plugs seem to need a specific version of open GL.
 
As strange as it sounds, we may want to move this thread to the main Sonar forum to get more people involved. My knowledge is small compared to some of the other forum members. It may take a while, but I have to think that if Sonar is crashing that much it must be something easy to find by process of elimination.

sojournx
True, I have not directly posted on any of the forums. I guess I just expected a bit more customer attentiveness from Cakewalk. If I pay for a nice stereo to go in my car and there are problems with it that weren't present with the
old stereo I would think I would take it back to the dealer/installer to make it right instead of hitting a forum and tearing into the dash to do the troubleshooting. No offence to the great folks in the forums but the first line should be the product support. Problem is, they are not responding.

You have payed for a nice stereo, but you have not really paid for the installation into your car... X2 -> Platinum upgrade price is lower then the price to install any stereo into any car, if I would like that is done by the authorized service
 
Back to the topic. Apart from your audio interface, ANY plug-in which you use is a part of Sonar and can trigger arbitrary memory corruption. I suggest you try to check either you can get such crash either without plug-ins at all or with delivered with Plat plug-ins only. Another possible point of failure is MS Runtime. Try to update all of them manually. I mean "Microsoft Visual C++ 20XX Redistributables", there are many of them (2005, 2008, 2010,2012, 2013, 2015). And all of them should be healthy. Quite boring, I know. But I guess once you get a replay from Cakewalk, that will be the first thing they ask you to do.
 
Different versions of Sonar are using different Runtimes, that is why one version can be "fine" while other is "crashing". Plug-ins also have runtime dependency. And some of them hope that correct version is already loaded and initialized by DAW and then fail/trigger crash once loaded into another DAW version.

There are several things to look at, but since these forums are not filled with reports of OTHERS having these constant crashes, it is extremely likely that the crashes are due to some local aspect of your system/configuration/Sonar installation/tweaks/etc.  In other words, this is likely GOOD news, because we can hopefully FIX it, with your help in helping us to help you.
 
So, us forum folks know nothing about how you installed things, or what things you have running, or any of that sort of information - other than what you provide to us, so until we get that all figured out, there will be some questions on that - so please do not get too frustrated at us for needing to get up to speed on YOUR particulars.... :)
 
(by the way - lots of us edit our Forum Profile Signature sections to include our system specs there, as it makes it WAY easier for others to see at a glance what sort of setups we each have.  If you look at the bottom of my posts, or many of the other members, it can give you an idea of what others may find helpful to know about YOUR system).
 
One more thing before I jump in to try to assist: The Cakewalk folks have indeed been in quite a bind with dealing with technical support issues - they rolled out some major changes to how support gets contacted, and there have been some serious burps with those changes, and while they are surely working feverishly to address both that set of nightmares and continued development and maintenance, there DOES indeed seem to be a bit of a backlog building with their ability to quickly respond to submitted tickets.  I have been a user of Cakewalk since the DOS days of Twelve Tone Systems, and FIRMLY believe they will get things worked out - and that things will work for the BETTER - if given some time.  They are a small company, so everyone is stretched tight when things like their newly rolled out technical support contact protocols have issues - addressing any issues like that pulls folks from doing other things, so please please please give them some time to address those issues - there are a BUNCH of forum folks who will work hard to help folks that can be helped. :)
 
OK - so some questions, and then some thoughts:
 
1) You indicated that you have read and tweaked - can you please detail what tweaks you have done to your system?  I am presuming you have read somewhere about some folks doing certain modifications to BIOS, Windows Registry, or whatever, and sometimes some of that information can be old and/or incorrect.  So, please detail any such tweaks you have made to your system.
 
2)  I see you are running Windows 8.1 - can you please tell me if that is completely patch current on maintenance (the critical/important ones)?
 
3) I think I saw in one of the above posts, that you have done an install of ASIO4ALL.  IF that is correct, am I to understand you do not currently have a separate dedicated audio interface for your system, at this time, and that is why you are running with ASIO4ALL?  OR, do you actually have an actual audio interface, and if so, which exact one, and what driver levels is it running on?
 
4) Please provide as much detail as possible on your installation/uninstall/re-install/etc., of Sonar Platinum.  For example, did you use the Cakewalk Command Center to perform the installation of Sonar Platinum?  If you did any uninstall/install again kinds of things, please detail how you uninstalled Sonar Platinum prior to attempting to install again.
 
5)  If you currently were to launch Sonar Platinum, WITHOUT opening any existing projects, does it at least get THAT far, to where it shows you the Start Screen?
 
6) If you DO use an audio interface, what Sample Rate and ASIO Buffer Size do you have set within the audio interface settings screen?
 
7) Which exact maintenance release of Sonar Platinum are you trying to run?
 
8) IF Sonar launches and gets to the Start Screen being displayed, if you close the Start Screen and simply hit the letter 'P' on your computer keyboard, does the Sonar Preferences dialog box open?
 
9) Is your Windows Default Audio Device ALSO set to point to ASIO4ALL?
 
10) Were there any particular error messages that you saw when Sonar crashed?  Did Windows also crash or just Sonar? And, have you looked at the Windows Event Viewer to see if there were any reported Windows errors there?  Some of that can be quite important.
 
11) Are any of your hard drives what they call 'Green'?  (meaning they can run at a slower spinning rate at certain times, depending on system demand on them).
 
Let's start with the above questions - sorry I have so many to start with, but hang in there - LOTS of folks have relied on assistance from forum folks to get things up and running smoothly - including ME - on countless occasions.
 
Bob Bone
 

I am also going to move this thread back to the Sonar forum, at least for the time being, as it is really a better place for starting to deal with whatever your set of issues turns out to be.
 
At this time, we have no confirmation that whatever is going on is because of anything specifically determined to be failing withing Sonar Platinum, AND lots more folks will see this thread within the Sonar forum - and hopefully jump in and help.
 
Lastly - I happen to be pretty freshly back from an almost month-long saga of surgery and post-surgical blood clots, so while I will do my best - I am a bit frail at the moment.  Hopefully others in the forum will come to your/our aid in figuring out how to get you up and running smoothly with Sonar Platinum.
 
Bob Bone
 
 

sojournx
.....my system definitely does not play well in the sandbox with ASIO :-).

Sorry, but can you please define "in the sandbox".  In the IT world, that has a meaning....  I just want to know what this means in this context

listed everything except his soundcard I believe.
what are you using for a soundcard ? this is important.

Come on Sojournx, you got us interested don't bail now.