grub里选择ubuntu9.04后屏幕显示：
Boot from (hd0,0) ext4 345303d6-2fe8-45f4-befa-878dbc10a47
然后就一直这个样子不动了，按电源键可以待机，热启动可以重启，但就是进不了进度条的界面，请问各位大大是怎么一回事？
前段时间更新过内核后也是这样，但这次没有更新内核，为何也这样呢？SOS，小弟先谢谢大家了！！！！

改过 menu.lst 了没有，用以前的内核及参数引导就可以了，

请问怎么改呢？我都不知道以前的参数是怎样的。还有，能告诉我为什么这样吗？谢了！

# menu.lst - See: grub(8), info grub, update-grub(8)
# grub-install(8), grub-floppy(8),
# grub-md5-crypt, /usr/share/doc/grub
# and /usr/share/doc/grub-doc/.

## default num
# Set the default entry to the entry number NUM. Numbering starts from 0, and
# the entry number 0 is the default if the command is not used.
#
# You can specify 'saved' instead of a number. In this case, the default entry
# is the entry saved with the command 'savedefault'.
# WARNING: If you are using dmraid do not use 'savedefault' or your
# array will desync and will not let you boot your system.
default 0

## timeout sec
# Set a timeout, in SEC seconds, before automatically booting the default entry
# (normally the first entry defined).
timeout 1

## hiddenmenu
# Hides the menu by default (press ESC to see the menu)
#hiddenmenu

# Pretty colours
#color cyan/blue white/blue

## password ['--md5'] passwd
# If used in the first section of a menu file, disable all interactive editing
# control (menu entry editor and command-line) and entries protected by the
# command 'lock'
# e.g. password topsecret
# password --md5 $1$gLhU0/$aW78kHK1QfV3P2b2znUoe/
# password topsecret

#
# examples
#
# title Windows 95/98/NT/2000
# root (hd0,0)
# makeactive
# chainloader +1
#
# title Linux
# root (hd0,1)
# kernel /vmlinuz root=/dev/hda2 ro
#

#
# Put static boot stanzas before and/or after AUTOMAGIC KERNEL LIST

### BEGIN AUTOMAGIC KERNELS LIST
## lines between the AUTOMAGIC KERNELS LIST markers will be modified
## by the debian update-grub script except for the default options below

## DO NOT UNCOMMENT THEM, Just edit them to your needs

## ## Start Default Options ##
## default kernel options
## default kernel options for automagic boot options
## If you want special options for specific kernels use kopt_x_y_z
## where x.y.z is kernel version. Minor versions can be omitted.
## e.g. kopt=root=/dev/hda1 ro
## kopt_2_6_8=root=/dev/hdc1 ro
## kopt_2_6_8_2_686=root=/dev/hdc2 ro
# kopt=root=UUID=85e39548-59a4-46f7-bdb0-baa866eebecb ro locale=zh_CN

## default grub root device
## e.g. groot=(hd0,0)
# groot=f5e2e63f-9364-42d7-9c83-5615a43d3f95

## should update-grub create alternative automagic boot options
## e.g. alternative=true
## alternative=false
# alternative=true

## should update-grub lock alternative automagic boot options
## e.g. lockalternative=true
## lockalternative=false
# lockalternative=false

## additional options to use with the default boot option, but not with the
## alternatives
## e.g. defoptions=vga=791 resume=/dev/hda5
# defoptions=quiet splash

## should update-grub lock old automagic boot options
## e.g. lockold=false
## lockold=true
# lockold=false

## Xen hypervisor options to use with the default Xen boot option
# xenhopt=

## Xen Linux kernel options to use with the default Xen boot option
# xenkopt=console=tty0

## altoption boot targets option
## multiple altoptions lines are allowed
## e.g. altoptions=(extra menu suffix) extra boot options
## altoptions=(recovery) single
# altoptions=(recovery mode) single

## controls how many kernels should be put into the menu.lst
## only counts the first occurence of a kernel, not the
## alternative kernel options
## e.g. howmany=all
## howmany=7
# howmany=all

## specify if running in Xen domU or have grub detect automatically
## update-grub will ignore non-xen kernels when running in domU and vice versa
## e.g. indomU=detect
## indomU=true
## indomU=false
# indomU=detect

## should update-grub create memtest86 boot option
## e.g. memtest86=true
## memtest86=false
# memtest86=true

## should update-grub adjust the value of the default booted system
## can be true or false
# updatedefaultentry=false

## should update-grub add savedefault to the default options
## can be true or false
# savedefault=false

## ## End Default Options ##

title Ubuntu 9.04, kernel 2.6.28-11-generic
uuid f5e2e63f-9364-42d7-9c83-5615a43d3f95
kernel /vmlinuz-2.6.28-11-generic root=UUID=85e39548-59a4-46f7-bdb0-baa866eebecb ro locale=zh_CN quiet splash
initrd /initrd.img-2.6.28-11-generic
quiet

title Ubuntu 9.04, kernel 2.6.28-11-generic (recovery mode)
uuid f5e2e63f-9364-42d7-9c83-5615a43d3f95
kernel /vmlinuz-2.6.28-11-generic root=UUID=85e39548-59a4-46f7-bdb0-baa866eebecb ro locale=zh_CN single
initrd /initrd.img-2.6.28-11-generic

title Ubuntu 9.04, memtest86+
uuid f5e2e63f-9364-42d7-9c83-5615a43d3f95
kernel /memtest86+.bin
quiet

### END DEBIAN AUTOMAGIC KERNELS LIST
这个是我的，不知道跟你是不是一样
你选择recovery试过没有

你在之前作了什么？

我应该什么都没做啊！就更新了一下！

又遇到这个问题了，请问高手怎么办？google了很久都没看到这个问题……怎么办？？？？有很多东西都没备份呢

我觉得，可能和UUID这个参数有关。（我猜的）

grub识别硬盘分区可以通过两个标志：
一个是位置，比如 hd(0,6)这样的格式。
另一个是UUID，比如 UUID=345303d6-2fe8-45f4-befa-878dbc10a47 这样的格式。

但是，据说UUID有时可能出错。

您可以试试，用liveCD修改一下menu.lst文件。
将 uuid 345303d6-2fe8-45f4-befa-878dbc10a47 这行改成 root (hdX,Y) 。（x和y根据您的硬盘而定）
将 root=UUID=345303d6-2fe8-45f4-befa-878dbc10a47 改成 root=/dev/sdaz。（a和z根据您的硬盘而定）

不过，这个方法是否见效，我不知道。

我的CD在公司忘带来了，赶明儿试试行不行再告诉你，总之谢谢了！