Linux Mint won't boot after a kernel panic. Can I get my files back?

Try an older kernel first. At startup, bring up the GRUB menu and look under Advanced options for Linux Mint. If an earlier kernel is listed, select its normal boot entry rather than the recovery entry.

The menu may appear if you hold Shift or press Esc during startup. The timing can be fiddly, so you might need to try both. If the older kernel boots, copy your files somewhere safe before changing anything else. A recent kernel update could be involved, but the error alone doesn't prove that's the cause.

If there isn't a working older kernel, boot from a Linux Mint live USB and use the file manager to look for your installed drive. Connect another drive and copy your important files over. If the installation is encrypted, you'll need its passphrase to unlock it.

Don't reinstall or format the internal drive before checking your files. A live session can also give you a way to inspect the installation if you decide to repair it later.

That unknown-block (0, 0) message can mean the kernel couldn't find or access the root filesystem. A missing or broken initramfs is one possibility, but a storage or boot configuration problem can also produce a similar failure.

If an older kernel works, check the installed kernel packages and whether the newer kernel has a matching initramfs before removing or rebuilding anything. Note the exact kernel version and any earlier boot errors too. Those details will help narrow it down rather than assuming a particular version is at fault.