So I backed up the vault, restarted obsidian, still getting the same problem. I restarted the computer, but I’m still getting the error (Windows 10 btw). I made sure I have write permissions to the vault and its contents. This happened shortly after I created a junction point (directory hardlink) to open the vault in another window. I’ve since scrapped that idea and trashed the hardlink. I’m not sure what happened, but think it’s probably related since this happened the same day.
Changes to .md files seem to be written to disk, but I’m still getting the error every time I make a change.
I’m going to try creating a new vault and see if the problem persists, then make a copy of my existing vault contents in a fresh directory and see if that solves the problem.