OK, here's what happened to me today while I tried to install Win7 Beta to dual boot on an existing XP system. I learned a valuable lesson through the mess and thought I would share.
My goal was to accomplish the dual boot without using any boot manager, such as Partition Magic or any other boot manager tool, to create the needed 2nd partition on a drive which has an existing OS installed in only one partition.
First, since the original HDD didn't have two partitions, I couldn't simply resize. I tried several tools on UBCD to resize then create a second partition. But, nothing I tried would work (or would have been destructive). :( So, I ended up using Seagate SeaTools (had Seagates drives to work with today) and cloned the drive to save it, then wiped the original drive and repartitioned it into two separate partitions, then copied the clone back into the first partition. Everything booted fine back to the original WinXP with the new partition showing in Disk Manager. I didn't notice at the time, but that second partion was an extended partition, a problem as you'll see below. I should have known better though. It had a drive letter and shouldn't have had one at this stage. :(
I went ahead and booted to the Win7 Install disk, not realizing what was going to happen. It went through installation using the Advanced method, installing into the 2nd partition all the way up to where it needed to reboot the 1st time. Upon reboot, it BSOD'd with Stop error 0x00000024. I rebooted again and got the same BSOD and stop error. :( So, I rebooted into WinXP to check and see if things were still intact. Everything ran fine there and the 2nd partition was still there with a drive letter. That's when I actually noticed that it was an extended partition. As I researched and read more, it had finally dawned on me that Win7 was going to need a primary, unformatted partition. DUH!!! So, I rebooted to the UBCD and deleted the 2nd partition information using Ranick.
After deleting the partition information through UBCD, I booted back to WinXP and looked at the Disk Manager. This time, it showed the additional partition as 'unalocated'. Great! I've made progress! :) I then told XP Disk Manager to make it a PRIMARY partition, but DO NOT FORMAT it.
I then rebooted to the WIn7 Install DVD and ran through the install again. This time, it ran through all the reboots, connected to the internet, downloaded drivers for everything and came up just fine so I could start playing around with it. It can see the WinXP partition. I just had to assign a drive letter to it. I rebooted back to WinXP and it can see the Win7 partition with a drive letter already assigned and I can see the files. Everything is up and running either way I want to go. Yippeee!!!!!!!! :D
Lesson learned:
(1) Don't use Seagate SeaTools to create the partitions. It creates one primary and one extended partition, formatting both to NTFS. I remember now, running into the same problem years ago with WinXP when it first came out. Can't let the tools format the drive or the install won't run. Funny, back then though, we got warned right at the start of the setup telling us it needed to format the drive after it was already formatted. The Win7 install didn't tell my one word about it. It just BSOD'd after the file copy process. :(
(2) Win7, or any newer OS for that matter, needs a Primary partition to install itself into, not an extended or logical partition. I knew that years ago, but had forgotten. Danged tools make things too easy now a days! ;)
(3) Next time I do this, after I have used Seagate Tools (or whatever tool the HDD manufaturer gives us) to create two partitions on the drive and copied the clone back to the first partition, go into WinXP and delete the 2nd partition so it shows as 'unalocated' BEFORE attempting to boot to the Win7 Installation DVD.
Of course, as the years go by, when Vista or Win7 become the older OS and we're trying to setup a dual boot with some new fandangled OS to test it, the tools to resize an existing single partition and create a new one in the empty space will be built into the OS (it's in Vista and Win7 now). We won't need SeaTools or any of the other HDD manufacturers counterparts 'tools'. ]:)