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Erasing MBR

Zainal062797 asked
I have installed a software utility that has created a small disk partition for its own purposes. Moreover, when I use FDISK, FDISK fails to show the new small partition and thus I cannot romove it. That is problem #1.
Problem #2 is that I have reformatted my disk and reinstalled Windows ME, but still parts of the utility is still there and causes some errors. I believe there are some instructions in the MBR that causes these problems.
So, what I need to do is to Wipe-off the entire drive. I have used some debug instruvtions in the past to solve similar problem, but I lost th einstuctions.
Does anybody know a utility that does this, or the debug instructions to achieve this task.

Thank you.
Watch Question

You'll need a DOS or Win9x boot floppy with fdisk on it.  From there, run "fdisk /mbr".  This will erase any information in the master boot record.  It should not harm your existing partition tables, so as long as your WinME partition is marked "active" this step will take care of your troubles without needing to reinstall the system.

A "low level" format utility will wipe all the drives contents including partition tables and restore the drive to it's "fresh from factory" state. You should use the utility made available by the manufacturer of the drive you are using.

For connor and seagate. www.seagate.com

For quantum and maxtor. www.maxtor.com

For western digital www.westerndigital.com


Look in their utilities and downloads sections.

If you have trouble, post the make and model and I'll look it out for you. Model number is important in some cases so check that.


Road Warrior

Road warrior beat me to it.  However, what exactly is the problem you are having or what is it you are trying to do and can't?  I see you may have created an additional partition that is not recognized by DOS.  I hope you have a Windows 98 Boot disk and do not LLF your hard drive and insert the ME disk when prompted for your OS boot disk.  Doing so will make the entire drive an extended partition and while it will work, ME will still want to reformat before using the drive.  Just a time delay.  If you don't mind running FDISK twice use the utility.

"I see you may have created an additional partition that is not recognized by DOS."

Ah, I misread and thought that the goofy partition had been removed.

Other possibilities include using Partion Magic to remove the mystery partition.  This would negate the need to re-install, but it is a commercial package.

Free solutions in addition to a manufacturer's utility include using a Linux boot disk with the Linux fdisk.  It is a much more sophisticated program that can delete any kind of partition.  There is no such thing as 'unable to delete non-Linux partition'.  Linux boot disks can be downloaded from a variety of sources such as www.slackware.org and www.redhat.com

Magarity, That's good.  Actually, some Linux Distros credit Partition Magic in their partitioning utility.
bbaoIT Consultant

no need to do low-level format, just use microsoft's delpart.exe do manage the mbr. fdisk /mbr is a good way to re-new the mbr.

It's not the MBR!  It is a Partition he created that is not recognized by DOS and therefor he will need to LLF the disk to recapture this space or find some other partitioning tool.  

agreed on the llf. the maxtor (maxllf.exe) will work on most drives (regardless of brand). you'll then need to fdisk & format the drive
bbaoIT Consultant

what we need is just to rewrite the 1st sector of the whole hard drive, why use LLF?! in fact, it is enough to use only debug and a few int13 calls.


Yes bbao.... That is what I have been talking about!
Debug... I told you I have used before and it is wonderful.
But the question is: What are the few simple instructions??! Do you have them?

bbaoIT Consultant

you mean the following? it will erase the first sector of the 1st hard drive. please use it carefully!!

a:>copy con delmbr.txt
f200 l200 0
mov ax,0301 ; write
mov bx,0200 ; from buffer 0200h to 03ffh
mov cx,1    ; for only 1 sector
mov dx,80   ; for the 1st hard drive
int 13
int 3



a:>debug < delmbr.txt
Zainal, you might want to bookmark this page of debug routines:
bbaoIT Consultant

it looks the routine is same as mine. again, use it carefully.

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