The following is a comprehensive list of error messages for the Stage 1:
This error message will occur if the Stage 2 or Stage 1.5 is being read from a hard disk, and the attempt to determine the size and geometry of the hard disk fails.
This error message will occur if the Stage 2 or Stage 1.5 is being read from a floppy disk, and the attempt to determine the size and geometry of the floppy disk fails. It's listed as a different error since the probe sequence is different than for hard disks.
This error message will occur if a disk read error happens while trying to read the Stage 2 or Stage 1.5.
This error message will occur if the location of the Stage 2 or Stage 1.5 is not in the area supported by reading the disk with the BIOS directly. This could occur because the BIOS translated geometry has been changed by the user or the disk is moved to another machine or controller after installation, or GRUB was not installed using itself (if it was, the Stage 2 version of this error would have been seen during that process and it would not have completed the install).
The error numbers correspond to the Errors Reported by the Stage 2 in the listed sequence.
The following is a comprehensive list of error messages for the Stage 2 (error numbers for the Stage 1.5 are listed before the colon in each description):
This error is returned if a kernel, module, or raw file load command is either trying to load it's data such that it won't fit into memory or it is simply too big.
This error is returned if the device part of a device- or full filename refers to a disk or BIOS device that is not present or not recognized by the BIOS in the system.
This error is returned if there is a disk read error when trying to probe or read data from a particular disk.
This error is returned if there is a disk write error when trying to write to a particular disk. This would generally only occur during an install of set active partition command.
This error is returned when a read is attempted at a linear block address beyond the end of the BIOS translated area. This generally happens if your disk is larger than the BIOS can handle (512MB for (E)IDE disks on older machines or larger than 8GB in general).
This error is returned if a linear block address is outside of the disk partition. This generally happens because of a corrupt filesystem on the disk or a bug in the code handling it in GRUB (it's a great debugging tool).
This error is returned if the sanity checks on the integrity of the partition table fail. This is a bad sign.
This error is returned if a partition is requested in the device part of a device- or full filename which isn't on the selected disk.
This error is returned if a filename is requested which doesn't fit the syntax/rules listed in the Filesystem Description.
This error is returned if a file requested is not a regular file, but something like a symbolic link, directory, or FIFO.
This error is returned if the specified filename cannot be found, but everything else (like the disk/partition info) is OK.
This error is returned if the partition requested exists, but the filesystem type cannot be recognized by GRUB.
This error is returned by the filesystem code to denote an internal error caused by the sanity checks of the filesystem structure on disk not matching what it expects. This is usually caused by a corrupt filesystem or bugs in the code handling it in GRUB.
Some of the filesystem reading code in GRUB has limits on the length of the files it can read. This error is returned when the user runs into such a limit.
This error is returned if GRUB was expecting to read a numbur and encountered bad data.
This error is returned if a device string was expected, and the string encountered didn't fit the syntax/rules listed in the Filesystem Description.
This error is returned if a device string is recognizable but does not fall under the other device errors.
This error is returned if the kernel image boing loaded is not recognized as Multiboot or one of the supported native formats (Linux zImage or bzImage, FreeBSD, or NetBSD).
This error is returned if the lowest address in a kernel is below the 1MB boundary. The Linux zImage format is a special case and can be handled since it has a fixed loading address and maximum size.
This error is returned when the Multiboot features word in the Multiboot header requires a feature that is not recognized. The point of this is that the kernel requires special handling which GRUB is likely unable to provide.
This error is returned if the boot attempt did not succeed for reasons which are unknown.
This error is returned if the module load command is used before loading a Multiboot kernel. It only makes sense in this case anyway, as GRUB has no idea how to communicate the presence of location of such modules to a non-Multiboot-aware kernel.
This error is returned if the initrd command is used before loading a Linux kernel. Similar to the above error, it only makes sense in that case anyway.
This error is returned if GRUB is told to execute the boot sequence without having a kernel to start.
This error is returned if an unrecognized command is entered into the command-line or in a boot sequence section of a config file and that entry is selected.
This error is returned if the file header for a supposedly compressed file is bad.
This error is returned the run-length decompression code gets an internal error. This is usually from a corrupt file.
This error is returned if the install command is pointed to incompatible or corrupt versions of the stage1 or stage2. It can't detect corruption in general, but this is a sanity check on the version numbers, which should be correct.