at least happened..after many and many fine installations,last night I tried sid . Reboot and I get a tragic " Hard disk boot sector invalid Press H to retry hard disk any other key for floppy"

I have tried several times by win2000 rescue consolle
CHKDISK
FIXMBR
FIXBOOT

no effect ..I'm only able to boot libranet by floppy ,which I wisely reinstalled creating a floppy

I tried to reinstall grube on /dev/hda with no effect..

Am I forced to format??
really hope not..thanks for help
ciaoo

Let me make sure I understand you correctly.

You have used both the xp fixmbr util and grub to write to the mbr and still get invalid boot sector error. I will assume that you are doing this correctly, and that nothing (like a bios setting) has changed the boot order to some hd other than hda first.

I would strongly recommend backing up all data on your hd _now_. It sounds like something may be wrong with the mbr sector on the hd. If this is the case the only solution is to replace the hd, iirc. Hope I'm wrong. You might try dumping the mbr with dd and looking at the signiture bytes at the end of the sector with a hex editor.

i'm afraid too..i only was able to install mandrake10.1 using lilo.
Infact when I tried to install debian ,I got a fatal error at step "install grub on MBR".
At reboot,I only got a long list of 99 99 99 99 99 99....and i remember is not a good sign
Thanks for your help
ciaoo ema

One more suggestion. After you backup whatever data you can, download and run the harddisk manufacturer's disk test suite. I would run all the tests it provides, including llf (write zero's to drive). This will of course wipe the drive clean, backup your data first. I'm pretty certain that this can't fix a bad mbr though. Good luck.

If you installed Debian and it borked your bootsector use NON debian based LiveCD to restore bootsector. Writing new lilo or grub may also help. In short, use rescue CD with options to reinstall bootsector or load your existing Linux. Slackware 10. for example uses second CD as rescue where you can forceload your exising system. Actually, FreeBSD multiboot loader deals with these problems no sweat