[X] upgrade interrupted and unable to boot: general error mounting filesystems

If you choose the recovery session in the boot menu, can you reach a recovery session?

No, I get the same general error message whether loading through the normal or recovery mode. The scrolling text always stalls with a message about a maintenance shell and the general error and ends in # prompt that is unresponsive to the keyboard. From there I can only power off/restart the system by pressing the button. Right now I'm running off a Live CD.

In the grub2 help, should the copy method be effective where the chroot method failed? That's provided the problem really is about grub and not corrupted system files when the upgrade was fatally interrupted, as someone on #ubuntu irc suggested today.

Is there a way to restore system folders and files without wiping user data? I was told no equivalent to Windows system file checker (sfc.exe) exist in Ubuntu and wouldn't have worked anyway with the level of damage I'm experiencing.

BTW: I used the chroot method, as recommended in the grub2 help, because I have separate system partitions such as var and home; that method is stated to be preferred over the copy methods.

I decided to try the copy methods in the grub2 help and when I mounted system partitions and used the sudo grub-install --root-directory=/mnt /dev/sdX, I got an installation finished message with no complaints from the system; YET I still get the same core dump for chroot and device not found error for upgrade-grub like I posted in pastebin. Everything is responsive until I hit those parts, even when I followed this other how-to: http://ubuntuforums.org/showthread.php?t=1581099

Also, I'm doubtful whether it's a grub2 problem, since rebooting into the boot menu command line again, I can find and list the content in my system folder, including /boot/grub and can use the set, insmod, linux and initrd commands without problems; YET loading either in normal or recovery mode continues to result in the general error and automatic start of maintenance shell that ends with an unresponsive prompt. Found instructions here: https://help.ubuntu.com/community/Grub2#Command%20Line%20and%20Rescue%20Mode

Please tell me there's a way to not bite the bullet and suffer data loss.

P.S.: I hope Ubuntu has that sporadic freezing (along with the unstable flash-plugin) bug set to severe and triage it accordingly ... if indeed it's a 64-bit issue. Not good. Looks good and runs well until that dreaded annoyance (to put it mildly) occurs.

I cut my losses overnight and did a fresh install overnight after reading similar general error problem in the Installation and Upgrade section of UbuntuForums.com where users had to resort to a re-installation. I did a backup of /home; hoping I got everything. Now to reinstall ALL those programs. :(

To answer your queries, the update was interrupted by a freeze-up during installation, not download, of packages; and I did use the simplest copy method and got the same general error upon reboot, even though the system didn't complain when I did the grub-install.

BTW: 10.10 is damn slick and fast! No freeze ups like previously so far, but that tends to come in later. Keeping fingers crossed. Hope I have a Ubuntu I can boast about and hope it stays so!

Thanks delance, that solved my question.