I got the Windows 10 Fall Creators Update and the 10.3.14 SPLAT update at more or less the same time, so I'm not sure which (if either) is the culprit, but neither of my MIDI keyboards (LX49, GAIA SH-01) now work in 32-bit Sonar (which I use because Musiclab's old MIDI plugins don't work in 64-bit Sonar).  Both worked fine before.  The keyboards still work fine in 64-bit SPLAT.  Has anyone else experienced this?  Any suggestions?
 
EDIT:
Ok, I need to correct what I said. I remembered I had a little oxygen 8 in the back of the closet. Pulled it out and it works fine in 32-bit SPLAT.

So my LX49, which uses a generic Microsoft driver that apparently was updated with the Fall update based on driver date, does not. And neither does my GAIA SH-01, which is still using the 2015 Roland driver, for MIDI. But it's not a global problem since the Oxygen 8 does.

Ok, makes no sense but here's how I can get MIDI from the SH-01. Can someone explain why?

I had it connected with the USB cable. Now I also attached the MIDI cables. In and of itself, that changed nothing. I then unplugged the USB cable. SH-01 no longer shows up in Device Manager. Did a legacy hardware install on the SH-01 (which is NOT how you install if you have the USB cable connected). Now I have the SH-01 showing up in sound devices, but with the yellow ! warning. I reconnect the USB cable. Now I also have an SH-01 showing up in device manager without a yellow !. The one with the yellow ! shows up immediately below it. I go into Sonar and I have MIDI from the SH-01. I can now disconnect the USB cable and I still have MIDI, but I cannot get MIDI without the MIDI cable connected. However, if I exit SPLAT and relaunch it, no MIDI unless the USB cable is connected. Also, if I delete the copy of the device with the yellow !, I no longer have MIDI from the SH-01; both device copies must appear in device manager.

Why does this work??

Do you have any other MIDI software with which to test your MIDI hardware?

EddieLotter
Do you have any other MIDI software with which to test your MIDI hardware?

I have FL Studio.  I was thinking it was only 64-bit now, bet there's also a current 32-bit version.  Guess what - the LX49 works just fine in it.  So does that mean it's a Sonar issue?  Sounds like it...

There are too many points of failure to know for sure yet.
 
Are you using legacy or UWP MIDI mode?
 
To change this in SONAR go to, Preferences | MIDI | Playback and Recording and change the MIDI driver mode and do some testing.

EddieLotter
There are too many points of failure to know for sure yet.
 
Are you using legacy or UWP MIDI mode?
 
To change this in SONAR go to, Preferences | MIDI | Playback and Recording and change the MIDI driver mode and do some testing.

Didn't even know about that setting.  I tried it both ways and it made no difference.
 
I also tried installing the September version of SPLAT over the October update - just for the 32-bit, left 64-bit alone.  Again no success.  That would suggest (not prove) that the Fall Creators Update is the problem.  But if so:
 
1. Why does the LX49 work (play MIDI notes) in 32-bit FL Studio?
2. Why does the Oxygen 8 work in 32-bit Sonar?
3. Also discovered that I can use the LX49 as a controller in 32-bit Sonar.  I just can't play MIDI notes.  So obviously the device is communicating with 32-bit Sonar.  Why no notes?

OK, stranger still.  I just used it in FL Studio - again no problem.  So I loaded 32-bit Sonar.  My default project template has a Drum track (synth and MIDI).  Lo and behold, it played notes!  So then I added another synth.  No notes.  Went back to the drum track.  No notes.  Closed the project and started a new one.  No notes.  Closed 32-bit Sonar and re-opened it.  No notes.  Right back to where I started - after 15 seconds of success.  Why???

Oh, by the way, I have also tried switching cables.  No luck.

OK, Cakewalk Support sent me the following suggestion:
 
 
 
"Hi Steve,
It sounds like there might be a hiccup in how 32-bit SONAR is reading the devices. Please try the following:
First, make sure SONAR is closed.
In the address bar for Windows Explorer, type: [font="'calibri',sans-serif"]%appdata%\Cakewalk and hit Enter.
Go to the SONAR Platinum folder. Rename the file called TTSSEQ.ini to anything else.
Then re-launch SONAR. That file will get re-written, and you'll need to re-enable your MIDI devices in the Preferences. Once this is done, go ahead and try recording MIDI again."
 
When I did as they suggested and then re-launched Sonar, once again I could play MIDI notes in the file that was initially created from my Normal template -until I did anything else (navigate away from the first and only MIDI track in the template, load another synth and MIDI track, etc.).  Does that give anyone a thought as to what I might try next?