i install ubuntu7.10 using livecd amd64
at beginning,i can boot to ubunyu from grub,bbut after several days,it can't.
the grub menu exist there,when i click the ubuntu to root,it display as follows:
error 17,can't mount selected partition,
i use livecd to rescue it as follows:

ubuntu@ubuntu:~$ sudo grub
Probing devices to guess BIOS drives. This may take a long time.

[ Minimal BASH-like line editing is supported. For
the first word, TAB lists possible command
completions. Anywhere else TAB lists the possible
completions of a device/filename. ]
grub> find /boot/grub/stage1
find /boot/grub/stage1
(hd0,8)

grub> root (hd0,8)
root (hd0,8)
grub> root (hd0,8)
root (hd0,8)
grub> setup (hd0)
setup (hd0)
Checking if "/boot/grub/stage1" exists... yes
Checking if "/boot/grub/stage2" exists... yes
Checking if "/boot/grub/e2fs_stage1_5" exists... yes
Running "embed /boot/grub/e2fs_stage1_5 (hd0)"... 17 sectors are embedded.
succeeded
Running "install /boot/grub/stage1 (hd0) (hd0)1+17 p (hd0,8)/boot/grub/stage2 /boot/grub/menu.lst"... succeeded
Done.

the first time ,suceed,but the next day,it happend again,i do the resuse again ,in the terminal has the same suceed message,but this time can't boot ubuntu from grub,
ps:i can boot windows from grub
why?
help!!

有没人知道啊，看来以后只能用虚拟机了先练手了！

没有报错吗，加上 nosplash 参数看看启动的详细过程。

可能我没描述清楚问题，在说一次，刚安装上进行了一些省级，安了几个常用软件，当天好好的，第二天再开机，就不行了。进入grub 的菜单，选择ubuntu就出现下列错误：
error 17:can't mount selected partition ,press any key to continue
我按照论坛上的方法，用livecd 进行修复，详见前贴，可以进入系统了，但到晚上再开机，又不行了跟上午一样的情况，用livecd再修复，终端提示成功了，但重启还是不行
但是我的windows可以匆grub进去
楼上说的加什么参数不知道是什么意思，能否把详细的命令给出来。本人菜鸟，谢谢！