PLEASE HELP! Getting "File note found - Result code = -43" when trying to import a valid audio file

Trying to figure out what the hell is going on with my computer of late. Just tried importing into a Logic session a valid audio file that played fine from my Desktop and got the message: "File Not Found - Result code = -43"...I've also been getting some weird MIDI weirdness (click going haywire until I reset audio in Audio Midi Setup), and, on one occasion, I recorded some Midi piano into a session only to have it not line up at all (even with Low Latency Mode enabled to ensure it picked everything up). I've tried repairing disks, resetting PRAM and SMC, etc., but it's still happening. I also moved the Logic session I'm working from to what I thought was a solid, additional internal drive to see if the other drive was failing and was the thing causing issues. What gives? Thanks for any thoughts/help! I'm concerned as I have a serious deadline and need to try and figure this out...

Much thanks -

D.D.

I also tried re-titling the file I was importing to just "test.wav" (to avoid special characters, as has been suggested before), and I STILL got the same error. Thanks in advance for any thoughts!

- D.D.

I just recorded some audio in the same session. While it DID record, when I tried to do the normal "Flatten and Merge" (which of course creates a new audio file), I got the SAME error (!) What gives? Thanks for any thoughts -

- D.D.

Ok - I moved the entire session to another drive and I can now "Flatten and Merge" and also import audio files again. I presume this means there's something going on with that other drive the session was previously on? What's the best way to check this? I'd already run First Aid on all disks.

- D.D.