Have 64-bit Sonar Platinum.  I also have Sonar LE which I used before the switch. A few days ago as MS was obviously gearing up to destroy my work, first, seven of the eight files on the "Recent" display disappeared except for the one I am actively working on. I didn't know what to make of it. Then the torrential 2-hr update started. 24 hrs later, the machine seems to have settled down after a dozen shutdown/restarts. Alas, I am getting the "Missing Audio" for mostly Platinum files whereas the LE which I left alone seem unaffected. This had happened when I had switched machines with LE but it was not crucial. Now, for songs released as singles I am just left with CD copies. If I were to fish out track by track, I wouldn't even know where to begin.
Also, even though it's been on the machine for almost a year, after the deluge, Microsoft decided that Cakewalk is "new" and Sonar LE, DreamStation xi2, and Cakewalk Pyro are unavailable.  

Check your Windows audio settings. The last two updates changed my default audio devices. First time it changed to my monitor's built-in speakers, which fortunately was obvious. The second time wasn't immediately obvious, as it had set the default to my integrated Realtek audio, which has always been disabled. Both times the fix was simply a matter of telling Windows that I wanted to use my Focusrite as my one and only audio device.

bitflipper
Check your Windows audio settings. The last two updates changed my default audio devices. First time it changed to my monitor's built-in speakers, which fortunately was obvious. The second time wasn't immediately obvious, as it had set the default to my integrated Realtek audio, which has always been disabled. Both times the fix was simply a matter of telling Windows that I wanted to use my Focusrite as my one and only audio device.

I'm so glad that I decided to throw away the three *free* upgrade copies I had for Windows 10, and go back to Windows 7. I did have to hack the registry in Win7 to prevent Microsoft from installing Win10 without my consent, but at this point I have five Win7, two Win8.1, and one Linux box and don't have to deal with crap like that.
 
My plan is to one by one convert every machine in the house to Linux, with the exception of my DAW, which I will eventually make dual boot Linux/Win7 as the January 2020 end of extended support date nears. I'll make Linux be the internet accessible OS, and dedicate Win7 offline only for DAW stuff.
 

Hmm, you don't have back ups? It's cerrtainly will fall on deaf ears if you failed to back up to an external drive all of the Folders with each song. You are using pre project folders are you not? 

Not asking for mercy, bro.
The issue was some .cwp lost their way to the audio; but not others, with no data or folder pattern to deduce why.
But I broke down and found the needles in the haystacks, so to speak.
Per project is the way to go along with .cwb etc. However, going back to my own experience with Sonar since 2007, it usually loses something when backed up on another drive.
The moral of the story is best to turn off wi-fi not just when recording but also when mixing. 

I turn off the NIC any time I record or mix.  I've had drop out problems in the past caused by it so I now disable it all the time. 
 
I tried a DAW controller on my iPad one time.  It was limited in features but the big problem was it had to have the internet connected since my iPad connected to my wireless router (which also has wired ports that I use for my desktop). 
 
As noted on another Win 10 thread, the Fall Creator's Upgrade did not "break" my system. 

fireberd
I turn off the NIC any time I record or mix.  I've had drop out problems in the past caused by it so I now disable it all the time. 
 
I tried a DAW controller on my iPad one time.  It was limited in features but the big problem was it had to have the internet connected since my iPad connected to my wireless router (which also has wired ports that I use for my desktop). 
 
As noted on another Win 10 thread, the Fall Creator's Upgrade did not "break" my system. 

Win10 sounds like some touchy and glitchy stuff to deal with for recording.  Using trusty old Windows 7 and REAPER, I have antivirus, internet, newsgroups, email, and web browsers all going while I'm composing and recording, and never worry a bit that it will possibly introduce a glitch into my project, or alter anything that is working.