This computer has Windows 7 and XP dual boot, the XP in first partition C:\ (Primary, active), Windows 7 in first of extended partition, prior to Fedora 12 installation I made an image of XP c:\ with True Image, then I started F12 installation and everything seamed going well, finally the F12 finished and to reboot, after the BIOS process and then the system got stuck: only the cursor blinking a top left, entire screen is black, and that's it, can't go any further. The entire hard drive was arranged like this: First partition is primary and active where XP resided, then the rest of drive is extended, first logical partition is Windows 7, 2nd logical is /boot for F12, then 3rd logical partition is f12 swap, 4th logical is F12 /. So I used the XP image file that I made before F12 installation and recovered the XP back into primary partition, then rebooted the system, this time the Grub is booting up and let me finish the last part of the F12 installation, the system finally dual boot with Windows.
Can any one tell me what happened? Looks like the F12 installation had altered the original primary partition that even grub can't boot up from it.