Boot Win7 from ntldr

Discussion in 'Windows 7' started by sebus, Aug 30, 2009.

  1. sebus

    sebus MDL Guru

    Jul 23, 2008
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  2. AUAnonymous

    AUAnonymous MDL Novice

    Jul 29, 2009
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    You could try using Chameleon bootloader if you don't want to use the Win7 one and ntldr isn't working for you.
     
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  3. sebus

    sebus MDL Guru

    Jul 23, 2008
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    Correct, if I select Mac OS from the ntldr I get second loader - Chameleon which gives me Mac, XP, Win7 options (from which each one works fine)

    Sure I could make Chameleon the default loader

    But I still want to get ntldr booting Win7

    sebus
     
  4. frwil

    frwil MDL Addicted

    Sep 22, 2008
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    Have read this article... some tips are definitely wrong. Bootsector's size of 512 bytes applies only to all FAT or Linux partitions, but the size of NTFS partition's bootsector is 8192 bytes. Then, why use a Linux LiveCD, when there're simple tools to extract bootsector, like mkbt.exe? One more thing: partition, which bootsector you load via ntldr, must be a BOOT partition (not a system partition), in other words it must contain bootmgr and BOOT folder in root. Thus. through ntldr you'll still load Vista's or 7's bootmanager, so it's kind of senseless circling booting.
     

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  5. ifeife2

    ifeife2 MDL Member

    Apr 25, 2008
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    #6 ifeife2, Sep 1, 2009
    Last edited by a moderator: Apr 20, 2017
    This method lets you keep NTLDR in your bootsector.
    add to boot.ini

    Code:
    C:\bootmgr = "Windows 7 Ultimate"
    
    I don't know any way to boot Windows 7 directly from grub menu or from NTLDR menu without calling upon the bootmgr file : (
     
  6. sebus

    sebus MDL Guru

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    That would be nice... if it worked.
    But of course does NOT (it is D:\bootmgr in my case above)

    sebus
     
  7. sebus

    sebus MDL Guru

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    Of course I can test it, and it could probably work.

    But that would do nothing good to my existing setup, would it?

    I really would like to understend what is happening during this early boot stage.
    If anybody has any idea how to debug it I would appreciate

    sebus
    No, I do not have RAID, how different one could format the SINGLE hard disk?

    sebus
     
  8. unawave

    unawave MDL Novice

    Mar 20, 2009
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    1. It can make clear if 512 byte sector is necessary or 8192 byte.
    2. If dual boot is working – install your Mac OS X and see if this is disturbing
    This step-by-step in a virtual machine is also a kind of debugging.

    Perhaps 10 different ways ? See picture.
     

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  9. os2fan2

    os2fan2 MDL Novice

    Mar 3, 2009
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    I used to boot vista by way of the NTLDR. It's tricky, but i will explain it.

    You could do it by way of having Vista/Win7 boot from its own active partition, eg setting the boot so that D: is the drive where win7 is installed.

    Each os would boot from its own partition, in essence.

    Now, you can boot other partitions from NTLDR by way of boot-sectors that initialise other boot devices. eg " Windows 7" =c:\bootsect.w61

    The utility bootpart might be of some use here.

    Another alternative is to get something like OS/2's boot manager, which boots other versions of DOS (like Windows NT, Vista etc) and Unix.
     
  10. unawave

    unawave MDL Novice

    Mar 20, 2009
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    Two remarks:
    • I just have tested a working triple boot system with XP, Vista and 7. Now I have changed the name of the boot sector file from "win7.bin" to "x-win7.bin" - but not changed the entry in "boot.ini". Now when I want to boot Windows 7 from the XP boot menu I get this error:
      "Windows can not be started, because the following file is missing or damaged:
      <Windows root>\system32\hal.dll"

      This error message has nothing to do with the real error (missing "win7.bin" file).
    • In this forum many people discuss about activating Windows 7 with special boot loader options (SLCI). Do you have used such special boot loaders for activating Windows 7 ?
     
  11. sebus

    sebus MDL Guru

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    Yes, all the soft Windows act*vators use loaders ie. grub4dos based modifications
     
  12. sebus

    sebus MDL Guru

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    Not really, we talking WinXP (NTFS), Mac (HFS+ MBR based), Win7 (NTFS)

    I see only ONE way (3 primary partitions, 1st one - XP active)

    sebus
     
  13. frwil

    frwil MDL Addicted

    Sep 22, 2008
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    Just checked extracted with mkbt.exe and HDHacker.exe bootsectors from NTFS partitions one at work, one at home and two on another HD at home, in each case both files are identical.
     
  14. unawave

    unawave MDL Novice

    Mar 20, 2009
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    OK. Then explain why "sebus" has found differences ?
    I think he has extracted different boot sectors.
     
  15. sebus

    sebus MDL Guru

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    #17 sebus, Sep 2, 2009
    Last edited: Sep 3, 2009
    (OP)
    No, I did NOT extract different bootsectors.
    I extracted 16 sectors from same Win7 partition using both tools
    Then checked then in HxD & they were different (of course they should NOT be different)

    I am not in front of this machine tonight, but will atatch both files as soon as I can

    sebus
    edit
    I rerun my bootsector extraction with hdhacker & mkbt and both files are IDENTICAL
    Which does change nothing really, as I still can not boot 7 from ntldr (press Ctrl+Alt+Del to restart error)
     
  16. unawave

    unawave MDL Novice

    Mar 20, 2009
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    Have you ever tried to extract only 1 sector (512 byte) and use this for boot menu ?
    Have you ever tried it without these boot loaders ?
     
  17. sebus

    sebus MDL Guru

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    If I use 512bytes, a single sector then my machine reboots INSTANTLY upon selecting Win7 entry from ntldr menu (as stated in first post)

    I do not use any ac*vation loaders. My BIOS is modded!

    sebus
     
  18. unawave

    unawave MDL Novice

    Mar 20, 2009
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    The modded BIOS should not be the problem.

    You said:
    When XP partition is active partition: XP boots fine
    When Windows 7 partition is active partition: Windows 7 boots fine.

    So I think your "grub4dos based modifications" has made some changes in boot sector of your Windows 7 partition.

    Again: Test it in a virtual machine - without you "grub4dos based modifications". You can test Windows 7 for 30 days without any activation. So you can test if the "bin-sector method" basically works and if the "grub4dos based modifications" creates the error.