MOTU MIDI Express 128 not recognized in MIDI Devices list

I have an Alesis SR16 drum machine connected to my computer through a MOTU Midi Express 128, using port 2.
I also have a Zoom UAC-8 Audio Interface, which also has a MIDI in and a MIDI out on it.
Everything was working fine until yesterday. I went into Edit/Preferences/Midi/Devices, and the MOTU MIDI Express 128 was no longer listed in the MIDI Devices list, as it had always been, up to that point.
I saw that: "MIDIIN 2 (ZOOM UAC-8 MIDI)” was listed as a MIDI device in the list, so I check it and hit Apply,  I got this error message: "MIDI device failure. The following MIDI port(s) could not be enabled. The port(s) will remain unchecked in MIDI device preferences."
I tried re-booting my computer and when I tried it again, Sonar crashed. It gave me this message:
 
Error – Unhandled Exception
A fatal error has occurred.
Module: C:\Users\Chris Haller\AppData\Roaming\Cakewalk\SONAR Platinum\MiniDumps\Blue Salsa 11-18-17_11232017_142810.dmp
Exception code: c0000005
Address: 00007FFDDB02BBDF:0000000000000000:0000000000000065
As a result of this error SONAR is about to exit abnormally.
Should SONAR attempt to save a recovery copy of your work?
 
Here are the troubleshooting steps I took, to no avail:

Swapped out the MIDI cables for the MIDI Express 128

Swapped out the USB cables for both the MIDI Express and the Zoom UAC-8

Disconnected the Zoom audio interface and restarted Sonar with just the MIDI Express connected

Connected the MIDI Express to my laptop, where I also have Sonar installed. It was recognized in the Preferences/MIDI/Devices list and worked fine with the program

Uninstalled and then re-installed Sonar on my Desktop computer 
Is there anyone out there who might be able to help me with this?
 
Thank you,
Chris Haller