Replying to
@itsfoss@mastodon.social I was getting that error a lot, only directly after a software reboot.
Turns out my pc doesn't fully pwoer-cycle everything when I do a software reboot (obviously 🤦) and one of my USB drives is permanently mounted, when it looks for the drive at boot it's already initialized and refuses to mount it (or even recognize that it exists). Turning off fast boot solved the problem.