I created a second partition on my main drove to install steam games, that way they persist in case I want to reinstall Linux or access from a portable windows install, but wanted it to mount on boot.
In partition manager, for some dumb reason, I presumed that flagging it as ‘boot’ would mean just that.
Obviously this was wrong, and now I can’t unflag the drive for some reason. It says it applies the changes but just leaves it flagged.
Can you unmount it? You may not be able to change the boot flag while it’s mounted.
If that doesn’t work, you likely can’t remove the boot flag while the system is booted. Try booting from installation media and changing the flag there.
Oh yeah, didn’t think about trying with a live media. Will do that
Whatever you do never flag your drives as system important (except the one with the OS), I found out the hard way when one died.