During the graphic boot phrase (rhgb), I noticed that I've been given the warning that "the boot sector data differs from its backup" and then followed with an array of digits. And I also been told that "the error was not automatically fixed". I've run fsck.ext3 on /dev/hda1 /boot but no error was reported, thus nothing fixed. I have 2 hard disks: The 30gb one (/dev/hda), installed with FC4, has 3 partitions: /boot, / and the swap on it, with grub installed; The 60gb one (/dev/hdb) used to be my /home/xia, but this afternoon I have it transformed into fat32 and then made a entry in /etc/fstab for it as /home/xia/Data. Then I installed Win98se on it. (I have to admit that I've been really missing some old-good games recently :p) In order to not have my data on the Linux disc messed during the installation of Windowz, I changed the BIOS setting of hda to "Not Installed", so I don't think I've hooked anything on hda. After the installation finished, I added a entry in /boot/grub/grub.conf. The dual-booting staff works fine and hdb is accessible with my normal user acc (there has been a minor issue though). So this "boot sector" output is the only thing bothers me now. I looked into /etc/rc.sysinit but failed to locate the line generating the error message. My *WILD* guess is that this is a GRUB problem, and there is one link: The first reboot of my Windows failed with only a string on the screen said "GRUB GRUB" then halted. So I had to run a "fdisk /mbr" and "sys a: c:" on hdb, and my first FC4 installation was on the 60GB disc (now as /dev/hdb). Is it that there might been some GRUB data left on the MBR of hdb and then replaced by me with "fdisk /mbr" so I've been told that there is a mismatch been found? I would like to have this error fixed in someway. There is some many other shitty things to do I really don't have much time to go thur the manuals; I also don't want to risk with my data as I don't have a rescue disk at hand (damn you LITEON cdrecorder! go to hell and rot; well, it IS cheap anyway :p) Thanks