Planetarion Forums - Master boot record, windows, partitions and stuff

Ragnarak · 5 Dec 2002, 18:47

I have 2 hard drives

One 20 gb that is split into 2 10gb partitions, C and E

One 40gb hard drive that i have winxp pro installed on, this is drive D

What i want to do is get rid of the partition on the small drive so i have one 20gb drive and one 40gb drive.

I booted into dos and formatted the C and E drives but then couldn't boot back into windows. I think the reason is because windows puts the boot record onto the C drive and formatted the C drive deletes this.

I reinstalled windows to the D drive but still have 2 partitions.

Is there anyway i can get rid of the partition without having to reinstall winxp?

Gayle29uk · 5 Dec 2002, 18:53

type fdisk at a DOS prompt, remove the relevant partitions, create a new DOS partition, format, problem solved.

meglamaniac · 5 Dec 2002, 19:23

Erase partitions C and E (Go to control panel -> administrative tools -> computer management -> disk management). You may recieve warnings about drive C being the active drive/primary system partition - override them. You may also recieve warnings about files being mounted on the partitions in general. Override them too.
Shove the XP CD in and boot off it.
Choose 'repair' (r) when prompted.
Log on to your windows installation (you'll need the admin password).
Type "fixmbr" at the command prompt.
Remove the XP CD and reboot.

Should provide you with a working MBR on your active disk.
You will then be able to boot windows normally and add the new partition to drive 0.

Ragnarak · 5 Dec 2002, 19:24

er

wouldn't that erase the MBR that i'm assuming is on C?

the only drive i want to keep and which has winxp on it is D

if i did what u say wouldn't i need to reinstall the OS once i formatted?

Ragnarak · 5 Dec 2002, 19:27

Quote:

Originally posted by meglamaniac

that would require a er how shall we say 'legal' version of xp wouldn't it

the cd i have it on is not bootable afaik

meglamaniac · 5 Dec 2002, 19:28

The OS is on D (which to windows is known as disk 1 (your second disk).
The other partitions are on Disk 0 (your first disk).

Erasing C and E will not affect D - you just won't be able to boot D until you have restored the MBR on Disk 0 (fixmbr). The MBR does not live in any partition - it lives in its own little sector. However, from what you've said it seems windows has plonked its bootloader on drive C. Once you've erased C and E the windows boot loader is missing so it won't boot. Fixmbr should sort this.
If for any reason it doesn't, you may need to create the partition you want on disk 0 at the recovery console (diskpart again), reboot, go back to the recovery console, format it, and then run fixmbr.

Even if THAT should fail for some reason (windows can be odd) then all you have to do is boot off the XP CD, and instead of choosing R for the recovery console go as if you are installing a fresh copy. It will then pick up the version allready installed and ask if you wish to do a repair install, to which you say yes.
20 or 30 minutes later everything will be back in working order and you'll have lost nothing.

Structural Integrity · 5 Dec 2002, 19:31

Or find yourself a "legal" version of Partition magic...

Ragnarak · 5 Dec 2002, 19:32

Shove the XP CD in and boot off it.

i can't do that with a copied version of xp can i....?

Log on to your windows installation (you'll need the admin password).

how do i logon? and what if i didn't set a password (left it blank)?

meglamaniac · 5 Dec 2002, 19:34

You do not need partition magic to erase and create partitions - only to resize them (and that's not a good idea for various reasons).
Most copied XP cd's are bootable.
Logging on to windows is part of booting the recovery console, you will be prompted.
If you set no admin password then there is no admin password - just press enter.

Structural Integrity · 5 Dec 2002, 19:40

No, ofcourse you don't *need* it, but it's quite handy as you don't have to mess around with that console. Thereby, the visualisation of the process decreases the chances of mistakes AND it lets you keep your old data.

Ragnarak · 5 Dec 2002, 19:49

megla i can't boot of the xp cd :/

meglamaniac · 5 Dec 2002, 19:50

None of the partion erasing/creating that i mentioned takes place at the console (except if fixmbr fails). It takes place in the Windows disk management applet, as I instructed.
Whatever you do, partition magic or not, you WILL erase the bootloader unless you erase E and resize C which as I have said is highly dodgy (I'll explain in a sec), so you'll have to go to the recovery console to fix it.

Why is resizing partitions dangerous?
Well, it depends on the filesystem.
FAT/FAT32 is the worst. If you resize that you have to maintain the cluster size. If you scale up and keep the cluster size the same, you have some serious issues including incorrect calculation of free space (leading to other problems) and slow/bad access.
NTFS is better, but there are still issues with free space.

Partitions were designed to be static. Resizing them is something they are not able to deal with properly.
The only program I've seen which can resize partitions safely is Norton Ghost, and thats only when it's cloning one drive to another. This is because the destination drive is being overwritten anyway, so it can rewrite the partition table as it goes to adjust the cluster size and the write the files to it. You cannot do that to a partition with files allready on it, because you then balls up the address of all the files so the FAT becomes a useless mess.

meglamaniac · 5 Dec 2002, 19:52

All is not lost!
http://support.microsoft.com/default...;en-us;Q311073

[edit]
Bad megla, I missed a step.
After fixmbr, you need to type fixboot.

Ragnarak · 5 Dec 2002, 19:54

Quote:

Originally posted by meglamaniac
None of the partion erasing/creating that i mentioned takes place at the console (except if fixmbr fails). It takes place in the Windows disk management applet, as I instructed.

i thought you said that i had to go into the console to run fixmbr...?

sorry for being retarded bout this ;(

meglamaniac · 5 Dec 2002, 19:56

You do.
fixmbr does not have anything to do with erasing or creating partitions.
You can happily delete and create your partitions in windows.
What you can't do is mess about with the boot records, so you need to be at the console for that.

And make sure you read the edit i put in my last post.

Ragnarak · 5 Dec 2002, 20:00

ok ta

one last thing

in the administrative tools, disk management part

how exactly do i delete the partition?

i right click on drive but delete partition is greyed out for C and D

meglamaniac · 5 Dec 2002, 20:23

gah - flippin' windows fluffy protection. Looks like you need to use diskpart at the recovery console after all.
I assume you deleted E ok? And don't delete D christsakes.

I can't walk you through it, as diskpart at the windows command line and diskpart at the recovery console are shown in 2 very different ways.
The one at the recovery console is nice and easy, and should show a list of disks and partitions when you start it (by typing "diskpart").
Just select the first partition on disk 0 (which will be C) and choose whatever option it is to delete it (should be shown at the bottom of the screen). You'll get a multitude of warnings no doubt but afaik it WILL let you delete it (eventually).

Ragnarak · 5 Dec 2002, 20:28

thanks for all the help

and if i'm not back online in half an hour i'm blaming you

Ragnarak · 5 Dec 2002, 21:11

ok

i made the boot disk, but using it takes me straight into windows, not to a recovery console

instead i used a win98 boot disk to boot into dos, used fdisk to sort the partitions, out etc

i now have a 20gb freshly formatted C drive and a 40gb D drive with winxp on it still

how do i get to the recovery console to run fixmbr/fixboot? can i?

the only way i can boot atm is by using the winxp boot floppy i'd just made

Ragnarak · 5 Dec 2002, 21:36

i had to boot into dos with win98 bootdisk and start winxp setup, let it load files onto C etc and then get to the recovery console from there

i fixed the mbr etc but then i had to do "bootcfg /add" to get it to recognise the windows installation and not just try to boot the setup stuff

it's all fixed now tho

sorry again for being so retarded bout this but i'd never had to do anything like it before

if i'm ever in loughboro i think i owe you a pint megla

meglamaniac · 5 Dec 2002, 22:00

Glad it worked out in the end - just as well you didn't need any extra help as I was watching an episode of 24 for the last hour or so (having finally found DVD 4 behind my desk, remarkably unscratched).

Pint? Pffffffft.
Mines a double ta - I'm taking you for all you've got!