It happen in no clue. Yesterday my Ubuntu 6.10 on Matsonic MB and 256mb memory ran smooth. But today the grub said it is missing the grub loader.
So We need Ubuntu CD or Ubuntu in flash usb. And boot from it…
Wait until the menu of Try or Install Ubuntu … appear and then press F6 to add single option. I meant just type the word single in the booting line option.
Because we don’t need the Ubuntu to enter gdm display, all we need is bash prompt only. After finish rebooting, there will be an option of
-normal mode bla bla
-netroot bla bla
-root bla bla
(sorry I have not capture its screen yet)
Choose netroot or root.
Then enter the grub menu and follow the instructions below.
grub >find /boot/grub/stage1 #it will display the boot partition
grub >root (hd0,1) #if your ubuntu located in first partition
grub >setup (hd0) #re-install the grub into MBR
Reboot your computer and you will have your grub back.
note: This trick will work too if you install windows after ubuntu. Because windows will replace the mbr with its bootloader, and cause ubuntu missing.