Hmm. This is new:
 

 
This is on a project that I mixed down yesterday in Jamaica Plain, without errors. All I did was mute some midi clips that were unnecessary... so it appears to be something in the K update. 
 
I'm rolling back to JP to check that I can mix-down in that version.
Bummer.
 
UPDATE: Mixdown succeeded in JP, as expected. I'll try re-installing K a bit later and try the mixdown again, when I have some time to experiment. Stay tuned.

Catastrophic failure, that was a new one... mhhh

Hopefully the Cats over at Cakewalk can sort this out.
 
 

Do you have any of the newly updated synths in the project (Zeta+2, Rapture Pro)?

Sorry to hear that. 
Do detail anything special with the project, bounce settings, etc.
We would like to investigate.
 
 

 
You'd think the first two sentences would be enough.   
 
Adding "Catastrophic failure" makes it sound like I should be alerting a federal agency. 

JonD
 
You'd think the first two sentences would be enough.   
 
Adding "Catastrophic failure" makes it sound like I should be alerting a federal agency. 

I used to get those in X2. Thank cripey all that has gone away since then but this doesn't look good. I'm sure it'll get sorted quickly if we already have Bakers digging into the threads.
 
The thing I dig MOST about the new Sonar is this quick, ultra hands on interaction from the company. That was not happening in the Roland days and it was rather disheartening.
 
I do hope for a quick response. I SERIOUSLY want to snag this update.

stickman393
Hmm. This is new:
 

 
This is on a project that I mixed down yesterday in Jamaica Plain, without errors. All I did was mute some midi clips that were unnecessary... so it appears to be something in the K update. 
 
I'm rolling back to JP to check that I can mix-down in that version.
Bummer.
 
UPDATE: Mixdown succeeded in JP, as expected. I'll try re-installing K a bit later and try the mixdown again, when I have some time to experiment. Stay tuned.

I'm seeing much the same thing, but without the warning window. Izotope IRIS2 doesn't work at all, replacing synths is causing consistent lockup (the window greys out and then eventual crashes). I'm getting phone-home pop-ups from both Sonar and Izotope.
 
I'll second the request asking how to roll back a version...saving that, I can always restore from backup (three cheers for daily incremental backups).
 
In short: Sonar was bulletproof for me from launch day until now. Currently, Sonar isn't useable in this state. Ouch.

I just exported (16 bit 44.1Khz) in Kingston from a previously mixed down track.  The only VST3 is Ozone 5.  No problems with the export.  There is no MIDI in the mixed down track.
 
"Catastrophic failure" is a long used computer term.  I think it originated with IBM. 
 
 

Relevant details, let's see... SONAR (32-bit) running on Windows 10 x64 with 8 GB RAM.
I install normally, but run Sonar "as administrator".
 
I rolled forward to K, and tried a mixdown of the same project again, without any changes. (I had just exported from JP without errors.)
 
This time it worked. No catastrophic error. OK, that's good. Let me check that it is the right version, in case I'm crazy... yup, Kingston.
 
Let me update the thread title to reflect the fact that I couldn't reproduce it (yet!). 
 
I'll keep working with Kingston at this point and see how it goes.
 
 Update: Made an edit to my project, re-ran the mix-down, no error. Looks promising.