Ubuntu12.04 install problem: the symbol `grub_xputs` not found

Can you give a bit more information on how you tried to install please. Normally if you want only Ubuntu on the one hard drive, if you followed the defaults and told the installer to use the entire drive you would have only teo partitions - one main partition and a linux swap partition which would be a couple of GiB or so. If you followed the defaults, you wouldn't have been asked for any partition information.

Thank you.
I installed Ubuntu12.04 to replace Ubuntu10.04.
The partition is like below:
/ 8G, /boot 100M, /tmp 1G, /usr, /var, /home, swap 2G

What I want is information about the partitions - you have given me the contents of the filesystem on one partition. Booting from the CD or USB stick, and using gparted from there will show you what you have.

It is looking as though you tried to partition alongside 10.04. Quickest answer might be to re-install and tell it to reformat and use the entire hard drive. If you have data you need to rescue, you should be able to access that by booting into the live-CD. Why you have ended up with nine partitions I just can't imagine, so you need to get rid of all of them and start over - which will be done automatically by the installer if you use the entire drive.

If you do use gparted to view the partition information, make a not of how each one is formatted - ie Ext4, Linux swap, NTFS etc. This information will possibly indicate what you have done incorrectly.

The 10.04 is covered by 12.04, not existing any more; the partition is not changed, however it's possible that I mounting differently this time because I cannot remember exactly, say I thought I have exchanged the mount point of /var and /tmp ; and swap is also another hdaX.
I'm now using the entire harddisk for Ubuntu12.04; all fromatted as ext4 besides swap.

Has that solved the problem?

The Gparted may help; unfortunately the screen go corrupted/slurry when started from live-USB (so I cannot see the information in Gparted clearly), just as what I encountered when I firstly installed 10.04, see https://answers.launchpad.net/ubuntu/+source/xserver-xorg-video-ati/+question/149279, however when I entered "echo "options radeon modeset=0" | sudo tee /etc/modprobe.d/radeon-kms.conf" in terminal, it went wrong, not successful as last time with 10.04

It's always frustrating to install Ubuntu, though it's stable to use it.

Can some command line to type after the Grub rescue prompt might resolve it?

I fixed it by using Boot-Repair; Thank you anyway.

Below is the description.
2nd option : install Boot-Repair in Ubuntu

Remark: this can also be performed from a live-CD or live-USB.

Either add ‘ppa:yannubuntu/boot-repair’ to your Software Sources via the Software Centre or, for speeds-sake, add it using a new Terminal session:

sudo add-apt-repository ppa:yannubuntu/boot-repair && sudo apt-get update
sudo apt-get install -y boot-repair && boot-repair

Boot-Repair can be installed & used from any Ubuntu session (normal session, or live-CD, or live-USB). PPA packages are available for Ubuntu 10.04, 10.10, 11.04, 11.10 and 12.04.