Win7 & WinXP Dual boot JAM


I have a Thinkpad W700 with 2 hard drives. I had Windows XP on drive1 and installed Windows7 on drive 0. It gave me a dual boot configuration with the following problem: I can NOT boot Windows7 unless it's in drive1 along with winXP in drive0. Any other configuration yields : "A disk read error occured. Press cntl-alt-del to restart". I really don't even want a dual boot configuration since I can boot either drive stand alone by hitting F12 and changing the boot order. It seems that the Win7 MBR must look to the WinXP mbr for its boot information and WinXP must preceed it in drive0.
Is there any sane way to KEEP my Win7 installation and just alter the MBR to boot independantly? I've tried a lot of conventional solutions (bootrec.exe /fixboot, recovery command prompt commands from the Win7 CD, Easybcd etc.) and nothing changes the status. It SHOULD be easy to just rewrite the MBR, etc. to just do a conventional boot, but it sure isn't as far as I can see. Any expert detailled help would be much appreciated.
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EasyBCD 2.0 latest build / Diagnostics / Change boot drive will copy back all the W7 boot files which have installed on the XP HDD. (default behaviour of a Windows install is to add boot files to an existing Windows "system" partition if it can see one).
You should then be able to boot W7 without needing the other HDD by putting it first in the BIOS HDD boot sequence.
You will need to put the NTLDR PBR back on the XP HDD if you want to boot that alone. Simplest way, after you've repaired W7 as above, is to boot into XP with the W7 HDD removed for safety, then use EasyBCD / Manage Bootloader / Uninstall the Vista bootloader.

That will give you 2 independently booting HDDs (possibly with an XP dual boot entry on W7 which doesn't work)
You can use EasyBCD add/remove from W7 to get rid of the XP entry from the BCD, and then (optionally) add a new one, letting it auto-configure if you want the convenience of a working dual-boot (it won't touch the other HDD, just copy necessary stuff to W7)

Check this out too
Tried it but no luck

I tried it using v It said that it completed successfully, but nothing's changed. I clicked change boot drive, selected C: (Win7 drive is drive C). Win xp is in slot0 and win7 is in slot1 but since Win7 is the booted drive, it's C. I do have the drives in sequence 0,1 in the bios but it doesn't matter (I just put the Win7 drive in slot 0, then tried slot 1) still no luck. This is a real toughie. Thanks a lot for your help, any idea why this is still failing? I am using Win7 Ultimate 64 bit version if that matters. Thanks! P.S.: Is it possible that the file(s) on the C drive may be locked since it's the drive with the running operating system? Should I possibly boot from the other XP drive and modifly what would then be the D drive? Just a shot.
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Screenshot attached (I hope)

Now XP won't boot because the ntloader is missing. Actually this is kind of strange since it was supposed to modify only the C drive NOT the D drive where XP was. Given these circumstances can I get back a valid boot config for XP now as well? Thanks again!


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You're still booting from the XP HDD. When you copied the boot files, did you do it from W7 or from XP.
If you did it from XP, then you must point to whatever XP calls W7, not what W7 calls itself. (EasyBCD translates BCD UIDs into letters as seen from the system it's running on)
If you have copied the files to the correct place (the W7 HDD) then you must boot from that HDD before they'll be used (the "system" flag tells you which boot files are in use)
I was running EasyBCD on Win7 when I copied files to drive C which should be Win7. So what exactly do I do to correct this? I can now only boot to Win7 with both drives in place (Winxp in slot 0, Win7 in slot 1). How do I find out what XP calls Win7? When I try to boot from the Win7 drive it won't work and now the same problem with the XP drive. The ONLY combination that will boot at all now is WinXP in slot 0 and Win7 in slot 1. I am very worried that I may lose both operating systems if I mess it up. Thanks
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If the "change boot drive" worked, you should see a boot folder in the W7 root with a BCD file (and a load of other folders) inside it. Copies of the same things in the XP root.
make sure folder options are set like this to be able to see them.
If the files are there and the partition is active, then it should work if you put that drive top of the boot sequence.
Can you expand on "it won't work" ? What messages ?
Remove the XP HDD.
Boot from your W7 DVD, "repair your computer" " startup repair"
Do the above line 3 times
That should make the W7 HDD independently bootable.
Put the XP HDD back, boot the W7 disk and add an entry for XP (if you want one)
Thanks I'll try it. One error I made, the message when booting XP is now a full black screen with alot of writing starting with "Windows failed to start" and referencing that the File:\ntldr is missing. Thanks


NO good. Simply did not work. At this point I just assume that I'm screwed. I've lost the ability to boot XP at all and Win7 won't boot without XP in front. If you can think of anything let me know before I'm forced to do drastic stuff. Thanks
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What didn't work ?
If you can boot W7 with both disks connected it's obviously all there.
If the OS is on one disk and the boot files on another which you remove, then MS startup repair should put all the boot files back, though it needs multiple runs to do it.
What did it say ?
Disk read error

It still gives the disk read error message when booted alone. The 1st startup repair found errors and allegedly fixed them. 2nd & 3rd times found no errors and did nothing. If it should but does not work, I'm still obviously screwed.
The only reason I can think of is bad blocks in the boot sector of the W7 partition.
Boot the W7 DVD again, but this time choose "command prompt" and run a chkdsk /r against your W7 HDD.
It will grind away for some time, but it should remove bad blocks from use.
Then try the startup repair again when it's finished.
OK will try chkdsk thanks.

OK I'll try that. Thanks.


chkdsk hangs on the 4th pass. Seems like a disk problem alright. I'm not sure what to do. I wonder if I can clone the disk without having the problem on the new drive. I'm running PC Doctor disk diagnostic test batter on the drive but have no idea if this will solve this kind of problem. What a pain! Any other ideas? Thanks!
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If you've not got a lot of time invested in customizing W7, your best bet is to reinstall, but this time, format the HDD (full not quick) to take the bad spots out of commission (and install W7 with XP disconnected to keep it all together this time).
Or clone the OS to external storage, full format the HDD, and copy it back if you want to keep custom stuff, then repair the boot.