I ran CCC as normal, then the upgrade stopped with successive registration failure messages relating to various MIDI plugins and the message 'Unable to register the DLL/OCK:RegSvr failed with exit code 0x3'.  After restart program failed completely with the message 'api-ms-in-crt-string|1-1-0.dll is missing from your computer.'
Sonar Newburyport was running fine until I closed it to  install this upgrade.  Obviously I will raise this with Support, but has anyone else had this problem?  I am running Windows 8.1 on an i5 laptop.

yup. me too. w7 64. had to roll back- it seems the sub model for the rest of the year ain't going to get much further than the dock

"Unable to register the DLL/OCK:RegSvr failed with exit code 0x3'." - This is Windows holding the regsvr process open due to pending/unfinished Windows updates.

'api-ms-in-crt-string|1-1-0.dll is missing from your computer.' - This indicates that Microsoft Visual C++ 2015 is not installed properly on your computer. This most likely cause is that it was blocked on initial installation via a pending Windows update/Windows process. 

Make sure all Windows Updates are properly installed and the system reset before re-installing 3.2016. That should allow VC2015 to install properly and SONAR will then run.

Edit: what Seth wrote

Can anyone here get Win7 Pro to update correctly? I have two comps with Win7 Pro, and neither of them will update. I have two with Win 10 Pro, and they update no problem through the same cable internet line. I even tried switching ethernet cables in case it was a modem port issue. I talked to the IT guy in my building over the weekend, and he was working the weekend because they have over 20 Win 7 computers that won't update. All were showing the same 0x3 error. I called MS support, and was on the phone for hours, and they couldn't fix it. They kept telling me that it could take hours to resolve itself, or that there was nothing wrong at this end, but even after I left it updating all night, it never installed even one update. I eventually bit the bullet, pulled a new hard drive, and upgraded my Win 7 to Win 10, but lost the use of my Lexicon PCM reverbs since they down't work under Win 10. Up until last week, I had no problem for years updating my Win 7 comps. One thing that did start last week is that I received a reminder to update to Win 10 on my task bar. 
 
Overall, seriously disappointed with the mess and the inability of MS to help fix the problem. I did a test where I installed Win 7 on a fresh drive to see if it would update so I could get use of my Lexicon plugs, but after running all night, it still wouldn't update.

Resonant Serpent
....upgraded my Win 7 to Win 10, but lost the use of my Lexicon PCM reverbs since they down't work under Win 10. 

 
Do you mean the Lexicon PCM VST Bundle? Mine works just fine under Win 10.
 

While we continue to support Windows 7, updates are getting increasingly difficult when we upgrade our tools. SONAR now uses the latest Microsoft redistributables and the Microsoft installers are finicky about having all the updates for Win7 in place.
Windows 7 is now almost 7 years old.  Microsoft has already stopped Mainstream support as of last year. At this point Windows 7 is on life support until 2020. This means that only important and emergency fixes to Win7 will likely be issued. As time goes on, incompatibilities will likely creep in and may or may not be addressed by Microsoft in a timely fashion.
I thing its a wise idea to consider upgrading while you are ahead rather than be faced with a surprise one day in the not too distant future.

Resonant Serpent
Can anyone here get Win7 Pro to update correctly? I have two comps with Win7 Pro, and neither of them will update. I have two with Win 10 Pro, and they update no problem through the same cable internet line. I even tried switching ethernet cables in case it was a modem port issue. I talked to the IT guy in my building over the weekend, and he was working the weekend because they have over 20 Win 7 computers that won't update. All were showing the same 0x3 error. I called MS support, and was on the phone for hours, and they couldn't fix it. They kept telling me that it could take hours to resolve itself, or that there was nothing wrong at this end, but even after I left it updating all night, it never installed even one update. I eventually bit the bullet, pulled a new hard drive, and upgraded my Win 7 to Win 10, but lost the use of my Lexicon PCM reverbs since they down't work under Win 10. Up until last week, I had no problem for years updating my Win 7 comps. One thing that did start last week is that I received a reminder to update to Win 10 on my task bar. 
 
Overall, seriously disappointed with the mess and the inability of MS to help fix the problem. I did a test where I installed Win 7 on a fresh drive to see if it would update so I could get use of my Lexicon plugs, but after running all night, it still wouldn't update.

Windows do seem to be making it difficult to use auto updates on win 7 since the release of win 10. I guess they are encouraging everyone to make the leap. You can manually download service pack 1 at this link if you don't already have it.
 
https://www.microsoft.com/en-us/download/details.aspx?id=5842&tduid=(85e63736685e746556e6825d4a75bcdc)(256380)(2459594)(TnL5HPStwNw-qb4lSwT.vJIQSng76m7PtQ)()
 

bapu

Resonant Serpent
....upgraded my Win 7 to Win 10, but lost the use of my Lexicon PCM reverbs since they down't work under Win 10. 

 
Do you mean the Lexicon PCM VST Bundle? Mine works just fine under Win 10.
 

This is the disclaimer at the Lexicon site:
 
"WINDOWS 10 OPERATING SYSTEM NOTIFICATION
 
The correct operation of the full, public release of Windows 10 is not yet verified by our development and test departments. As a result, support for Windows 10 is not currently offered for Lexicon digital hardware, software applications, or third-party proprietary software used with our products. We cannot confirm a date for providing support for Windows 10, but note that full software testing and verification is underway.
 
To keep your system working normally with the affected products, Lexicon strongly recommends waiting before upgrading your operating system to Windows 10 until full software testing and verification has been completed."  
 
I originally tried to load the PCM reverbs in Cubase, and they wouldn't load. Ending up taking the program down. I then saw the disclaimer at the site, so didn't try them in another host.
 
So, the PCM reverbs are working in Sonar without a hitch?

Noel Borthwick [Cakewalk]
While we continue to support Windows 7, updates are getting increasingly difficult when we upgrade our tools. SONAR now uses the latest Microsoft redistributables and the Microsoft installers are finicky about having all the updates for Win7 in place.
Windows 7 is now almost 7 years old.  Microsoft has already stopped Mainstream support as of last year. At this point Windows 7 is on life support until 2020. This means that only important and emergency fixes to Win7 will likely be issued. As time goes on, incompatibilities will likely creep in and may or may not be addressed by Microsoft in a timely fashion.
I thing its a wise idea to consider upgrading while you are ahead rather than be faced with a surprise one day in the not too distant future.

I didn't realize that mainstream support had ended. Thanks for the heads up. I actually like Win 10, a lot, but wanted to roll back because of the Lexicon plugs. If I can get them to work, then all is good.