Changing XP/Vista Dual Boot to Single Boot Vista

Good morning everyone.
I'm hoping that someone can help me with this problem while I still have some hair left!
I have a dual boot PC with XP Prof installed first on C: and then later added Vista Ultimate which was installed on D:
Each OS becomes C: when it's booted and I'm using the Vista boot manager.
If I remove the first drive (XP) and select to boot from the Vista disk, I get a "Disk Read Error Occured press Ctrl-Alt-Del to Restart" error message. I was wasn't suprised by this and proceeded to boot from my Vista install disk. At this point, the repair process made some changes and it rebooted. After reboot, I got the same error message though Vista repair now showed the Vista partition on C: Following all the recommended help, I tried to rebuild the BCD (bootrec/rebuildBCD) but it didn't find any OS. Renaming BCD in Boot dir corrected this and bootrec then worked OK. System still shows Disk Read Error. I then went through all the recommendations of bootrec/fixmbr, bootrec/fixboot and bootsect /nt60 sys /force and none of these fixed the boot up error message.
If I replace the XP drive, Vista boot fine. I have tried the new Beta of EasyBCD as it has a feature to choose the boot drive in the Diagnostics Centre. I tried this, choosing C: as my boot drive as I was running in Vista at the time (not sure if this was right though) but I've still got the Disk Read error.
I don't really want to keep XP as I wanted to install Windows 7 on that drive but it is an enormous task to re-install my Vista as it is full of PLC programming products etc that take an age to install. I tried using the Vista built in full backup but this has backed up C: and D: (XP) and will only recover to C: and D:
Sorry for the long post. I'll keep an eye on my email and answer any questions ASAP.
Thanks for your help.
Thanks for the suggestion Terry but I've already tried that and it didn't work. I've tried it twice and it's not playing ball. Earlier today I also tried gag4.10 and while it worked with my XP partition, it could boot the Vista partition. Yet the Vista partition is what I'm using now, which is fine if it's D:
I'm sure I'm missing something fundamental and stupid. Cloning the drive exibits the same problem and the drive seems to check out OK.
I'm not really sure which part of the boot sequence generates the error message "Disk Read Error Occured press Ctrl-Alt-Del to Restart". If it's the Bios, would that suggest that there is something wrong with the master boot record? The drive is set active and I believe gets the System drive status if it's selected to boot in the bios.
Though drastic, I may try installing clean Vista on a spare drive and then look at comparing the vital bits.
I could have re-installed everything by now but it's got beyond that; I am now hunting Moby Dick and won't rest till he's dead!
Sorry, I obviously didn't read your 1st post carefully enough.
Can you post a Disk Management screenshot and copy/paste the EasyBCD "display settings" output in detailed mode.
Don't worry about it Terry, I'm seriously questioning my sanity and appreciate you help.
Images as requested below:
Sorry but File Upload didn't like my snipped jpegs for some reason.
Thanks again for your help.
Best regards,
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Can you use the paperclip icon from "go advanced" (below the quick reply box) and upload .jpg as an attachment. (you can just copy/paste the text from "display settings" - no need for graphics)
CG appeared for a short while earlier and fixed the server problems so I thought the upload problem would have gone too, but I see not.
Strangely, your missing screenshots appeared in the previous post, so I've seen them twice now.
You still have XP flagged as "system", so obviously the "change boot drive" didn't work.
Did you do it when both disks were connected ?
What did it say/do ?
Which drive is 1st in BIOS boot sequence ?
The change boot drive function said it had completed OK.
Yes, I did do it while both were connected. I did wonder if it was possible that it could be confused by the drive letters switching.
These shots were taken while in Vista which starts off as D: but is C: when in Vista. The System Disk is the XP drive which starts as C: but becomes D: when in Vista. The drive letters are reversed when booting XP.
For completeness, I will try changing the boot drive to D: which is the Vista drive at switch on. should just be able to fit that in before feed time and I'll let you know if it worked.
Drive letters in EasyBCD are "as seen by the running system", so you should be changing from D to C.
When you disconnected XP and booted the Vista DVD, did you run "startup repair" 3 times ?
It has several things it needs to create and is only capable of doing one per pass.

(disk letters are not "real", just entries in the registry of the running system, so it's perfectly normal that different systems see them differently)
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THe first boot did some repairing but the second boot said nothing needed repairing and gave the "If you have recently connected a USB device or whatever, disconnect it and try again", so I never bothered with another boot.
I'll also give that another try.
Hi Coolname007,
Following any attempt to repair/alter/reconfigure the Vista drive, I've been plugging it into SATA port 1 and making it the first drive in the boot sequence. My motherboard is a P5Q-PRO and I can only put one fixed drive in the priority boot sequence. I believe you can put multiple removable drives in the HD drive sequence table and then the first available in this list is placed in the master boot order, along with your optical and floppy drives. For example, if I put Vista as Disk 0 and XP as disk 1 in the drive boot Table, Vista produces the error message and then hangs. It does not then proceed to boot XP on Disk 1, but I'm fine with that anyway; causes less confusion.
I've also been removing all of the other OS drives to avoid confusion. I just left my data and backup drives. The previous screen shots show the XP and Vista drive only while booted into Vista. Interestingly, in the prev screen shots, Disk Mangement was showing Vista as disk 0 and XP as Disk 1. This was the first time they had appeared in that order and swapped back after the next reboot to Vista on Disk 1. They have always been in the same boot order and in the same SATA ports when in together.
I'm starting to think that it's nothing to do with BCD etc,but more to do with the bios not recognising it as a valid or bootable drive? Do we know which part generates the "Disk Read Error Occured press Ctrl-Alt-Del to Restart"?
Another possibilitly is based on a cause I found in another thread. I forget the exact cause but a guy found that some of the boot files had inadvertently moved to an area on the drive, beyond the boot sequence's capability. The fix was to steal file area from a file that didn't matter, in the readable range of the boot stuff. I'm not sure if this could explain my problem but I'm willing to try anything. I'm working on the Vista clone now and if I don't fix it by tommorow night, I'm putting a clean Vista on this drive and then i'm going to export the key sectors for comparison using MBRFIX.
Further to last nights post, i've done a clean install on a second drive and have grabbed the first 2000 odd bytes of each drive for comparison. I figure that I can gradually install stuff in the new drive while I learning what the hell is going on!
The master boot record sort of looks fine, with only the drive signature and the partition info differing between the first 512 bytes. I didn't expect to see much difference between the partition info on each drive but they differ a bit. The clean install was done on the drive I had originally cloned but had since deleted the partition. The Vista install disk created a new partition on it and created it starting at Head 20, Sector 21. The offending Vista drive has its partition starting at Head 01, Sector 01. This may just be a red herring or vista install may have moved it beyond old data?
The main error message I've been getting sits at 7F80, along with text for two other messages; "BootMgr is Missing" and "Bootmgr is compressed". I'm not sure which prog resides at this area but it's the same for both drives. (See attached file for capture).


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Well, it seems to be pointing to me having an invalid PBR (Partition Boot Record) on the Vista partition. Apparently, if a partition is already formatted and then has Vista installed in a dual boot configuration, the old PBR can be left on the drive. It doesn't matter when the drive is in a dual boot configuration as the PBR of the system drive is always used, along with Bootmgr on the system drive. Updating the MBR of the second drive allows it to call the PBR on it, but if it's still a none Vista PBR, it will be looking for NTLDR etc. This may explain my problem but I'm still none the wiser as to whether it can be fixed.
Can anyone confirm if EasyBCD updates or replaces the PBR and if not, whether anything else can?
Ok. If the Vista partition's PBR is the problem, then just boot into XP, run EasyBCD, go to Useful Utilities, open up the Power Console, and do:

bootsect /nt60 X:

where "X" is replaced with the drive letter of the Vista partition as seen by the booted system. That will rewrite the bootsector code on the Vista partition, and it should fix the problem.


Thanks Jake, I'll give it a go later tonight.
Will this write a Vista PBR to the drive then? Some bits I've read indicate that while bootsec/fixboot should fix the PBR, it may write an XP version or mend the XP one that's already there.
Hi Terry,
I apologise for all the stupid questions and feel free to tell me to give up.
OK, so are we saying that Bootsect /nt60 will repair the Vista drive PBR or will it replace it with a Vista specific one? I ask this as I've already gone through all of these commands and they didn't fix it. The only thing left to think is that they only fix/repair whats there. I don't remember but the drive may have been formatted in XP prior to installing Vista as a second boot. If this was the case am I stuffed?
Whats your current configuration, both disks connected ? which one 1st in boot sequence ?
It doesn't matter what you formatted the HDD with, if Vista installed to it as system, or you did a Vista startup repair with only that disk connected, then the MBR/PBR will be Vista's.
If you tried to startup repair Vista with XP still connected as "system", then it will have operated on the XP disk, not touching Vista.
If you've got an XP PBR on the Vista HDD, you should get an NTLDR error message when you boot with that HDD first in the BIOS.
Have you done "startup repair" 3 times with only the Vista HDD connected ?