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.
Yeah it was pretty silly, I for some reason blanked on the fact that boot is an important flag. Thankfully booting the live media worked
From Wikipedia, the free encyclopedia
Linux is a family of open source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991 by Linus Torvalds. Linux is typically packaged in a Linux distribution (or distro for short).
Distributions include the Linux kernel and supporting system software and libraries, many of which are provided by the GNU Project. Many Linux distributions use the word "Linux" in their name, but the Free Software Foundation uses the name GNU/Linux to emphasize the importance of GNU software, causing some controversy.
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