hi i was using debian etch and yesterday i installed ubuntu hardy and my system has 2 os. vista and hardy. when i try to restart and choose ubuntu sometimes i got this error and im going crazy. i shutdown 3 or more times and then it goes normal. how can i fix it?
here is the error: http://img232.imageshack.us/img232/7550/1000634vk8.jpg

Seems like Ubuntu is not playing along nicely with ACPI. Try appending acpi=off to your kernel parameters at boot up. You can also add acpi=off the kernel parameters of your default grub entry so that you don't have to enter it repeatedly at boot up.

I do not recognise your exact error but it looks like a problem with acpi. Disabling acpi when booting might temproarily help. Then you will know if acpi is the problem.

(Acpi is good, so if it does turn out to be the problem, look into how to configure acpi differently to avoid the error.)

How to disable acpi? Add it to the kernel boot parameters for grub.

To test the parameter, you can edit grub when booting (the changes are not saved):

• select your hardy from the grub boot menu when booting, then press 'e' (for edit)
• select the line starting with 'kernel' and again press 'e'
• insert a space after the last entry then add the parameter (such as 'acpi=off')
• press Esc to go up a level
• press 'b' to boot

To permanently change the boot parameters, you need to edit the line starting with 'kernel' in the configuration file /boot/grub/menu.lst ... Leave a space after the last entry in this line then add acpi=off (or whatever parameter you need)

You can find an extensive list of kernel boot parameters here if you want to experiment or research for yourself.

EDIT sorry to double up on your post reddazz, I type slowly

exact error is given. just changing is starting number. sometimes start with 16, 17, 19. it is changable.
i dont want to disable acpi. but ill try it. thanks.

i guess i fix it. first i installed 7.04 and then i upgrade the distro. sometimes if you did like this maybe you have some problems.
i install directly 7.10 and dist-upgrade and i got no problem.