Mac can't see WIN7 installation after removing drive with XP installation: SOLVED

Discussion in 'Windows, Linux & Others on the Mac' started by tugger, Sep 29, 2010.

  1. tugger macrumors regular

    tugger

    Joined:
    Apr 14, 2005
    Location:
    KTLH
    #1
    Yeah, I really dislike reading long-winded posts too, but this is the simplest write-up I could do on this weird problem. Thanks if you have the patience to read through it.

    I have a Mac Pro with 4 internal drives. About a year ago I did a BC installation of Windows XP Pro on one drive, and recently I did a BC installation of WIN7-64 on another drive. The drives are:

    Bay1: 1 partition: SL (Mac OS Extended Journaled)
    Bay2: 2 partitions: WIN7-64 (NTFS) / SL backup (Mac OS Extended Journaled)
    Bay3: 1 partition: Data (NTFS)
    Bay4: 2 partitions: WIN-XP (NTFS) / Data (Mac OS Extended Journaled)

    This may or may not be important, but NTFS-3G is active in my Snow Leopard installation.

    To boot into Windows I hold the option key down on startup and am presented with:

    Snow Leopard / Snow Leopard Backup / Windows

    I select Windows and am then presented with a DOS-like screen giving me the choice of booting into Windows 7 or "Earlier version of Windows". All fine, and I can elect to boot into either WIN-XP or WIN7.

    I bought Acronis True Image Home 2011 and the Plus Pak (to handle GUID partitions) and a 2T drive to use to back-up the 2 Windows partitions.

    I removed the drive holding data only from Bay3 and inserted and partitioned the new 2T drive as follows:

    1-HFS Journaled
    2-NTFS (to hold the Windows backups)

    I then used Acronis to individually back up the WIN7-64 and and WIN-XP partitions to the NTFS partition on the 2T drive. That all went fine.

    I obviously want the 2T backup drive available all the time to do backups. Since I don't use WIN-XP much anymore, and I also need the data on the drive that was in Bay3 to be available, I removed the drive with the WIN-XP partition (Bay4), moved the 2T drive into Bay4. Then I put the data drive back into Bay3.

    Here's the problem: Now, when I reboot the Mac and hold down the Option key to select Windows, it no longer appears as an option. Only my two SL installations are presented. Ditto with the Startup Drive function in System Preferences.

    On a hunch, I removed the new backup drive from Bay4, put the drive with WIN-XP back into Bay4, and everything works as before.

    So it seems to me that there is something on the WIN-XP drive that enables the Mac to see both the WIN-XP partition and the WIN7-64 partitions as bootable. Remove the disk containing WIN-XP and the Mac can't see the WIN7-64 installation either.

    How can I get the Mac to recognize the WIN7 installation when the drive containing WIN-XP is removed from the Mac? Is there a fix for this?

    Thanks.

    Jev McKee
     
  2. Berlepsch macrumors 6502

    Berlepsch

    Joined:
    Oct 22, 2007
    #2
    I'm not sure if I can really help you, but I'll try.
    First, your Win7 is most probably not bootable at the moment, because its bootloader was installed on the XP partition. You need to repair the Windows 7 installation from the install disk to fix that.

    If I were in your place, I would (after backing up the Win7 installation) run the boot camp assistant and see if it recognizes the Win7 partition. If that works, you can probably boot from the install CD and use the startup repair option.

    In case that you can't select your existing Windows partition, you can also try and create a new boot camp partition with the boot camp assistant. It can be rather small, because it only needs to hold the win 7 boot files. Again, after booting from the Windows install disk, you can try to run the startup repair and hopefully make your Windows bootable.
     
  3. balamw Moderator

    balamw

    Staff Member

    Joined:
    Aug 16, 2005
    Location:
    New England
    #3
    I would concur with the backup and startup repair.

    This bit I'm less in favor of. BCA is really only useful in single HDD configurations.

    What I usually find helps for these more complicated cases is to simplify the system. Remove all non-essential drives, make it work and then add back in the stuff you want.

    B
     
  4. Berlepsch macrumors 6502

    Berlepsch

    Joined:
    Oct 22, 2007
    #4
    The problem, as I understand it, is that you can't boot a Windows install disk directly from Mac's EFI. Instead, you need to have boot camp prepare a BIOS environment so that Windows can actually start.

    That was the idea behind my second suggestion. Here, boot camp creates a small partition for windows, which will be sufficient to boot the DVD and hopefully fix the non-functional Windows 7 system.
     
  5. balamw Moderator

    balamw

    Staff Member

    Joined:
    Aug 16, 2005
    Location:
    New England
    #5
    I get what you were after.

    However, the ability to boot from MBR is in the firmware not BCA.

    You are quite correct that BCA helps you create a hybrid GPT/MBR partition scheme, but my point was that this only matters in a single HDD system, which this is not.

    I have personally installed Windows Vista and 7 on dedicated drives on Mac Pros simply by removing the OS X HDD, inserting a blank HDD and the Windows install disc and rebooting holding Alt/Option.

    Also, Win764 is GPT/EFI aware. For recent Macs that are officially able to run W764 the BIOS/MBR compatibility layer of Boot Camp is not needed.

    B
     
  6. Berlepsch macrumors 6502

    Berlepsch

    Joined:
    Oct 22, 2007
    #6
    Okay, I haven't really played too much with boot camp, using a single HDD iMac. What I remembered hearing is that Apple's implementation of EFI and Microsoft's EFI support in Win 7 didn't work together; but obviously I was wrong.

    So if you can boot the Win 7 installation DVD without boot camp support, than this is of course the first thing to do for our OP. Hopefully it will find the broken partition and fix it; temporarily unplugging the other disks is certainly a good idea.
     
  7. tugger thread starter macrumors regular

    tugger

    Joined:
    Apr 14, 2005
    Location:
    KTLH
    #7
    Guys, I really appreciate your advice. Here's what I've done:

    Ran a complete backup of my WIN7-64 installation.

    Next, I removed the hard disk with the WIN-XP installation (to keep the rest simple -- thanks for this suggestion).

    Then I ran BCA. It sees the two partitions on the disk with Windows 7:

    1- Snowcat Backup (Mac OS Extended Journaled)
    2- BOOTCAMP (NTFS)

    It gives me the options to erase the disk and install either a single Mac or a single Windows partition. It does not give me the option to create another Windows partition, I guess because it sees that one is already there. Anyway, BCA sees the WIN7 installation (or at least the Windows partition).

    The Startup Disk system preference obviously still does not see the Windows 7 installation as a boot option.

    Next, I started the Mac from the Windows 7-64 installation disc with no problem. I can get to the Repair and Restore options. The install disc sees the Windows 7 installation and gives me the option to run automatic startup repairs.

    So, now what's the next step? Run the automatic repairs? Will this create a new MBR on the Windows 7 installation?

    Thanks again for your help.

    - Jev McKee
     
  8. balamw Moderator

    balamw

    Staff Member

    Joined:
    Aug 16, 2005
    Location:
    New England
    #8
    True for older Macs not on the official W7 64 compatibility list http://support.apple.com/kb/HT1846?viewlocale=en_US The machines I was using were 2008 and 2009 Mac Pros.

    Since the OP already has W7-64 loaded it is a good bet that they either have a later model, or know how to make W7-64 ignore the incompatible EFI and boot via MBR using "Jowie's method" of modifying the install DVD.

    You are still using Boot Camp, just not necessarily the Assistant.

    Even for Windows that only supports MBR, all you need is Disk Utility and the Boot Camp components that live in the firmware. This is how many of us have installed from unsanctioned versions of Windows. (like XP MCE, XP Upgrade, etc...).

    Insert (almost) any bootable CD and hold down Alt/Option. You can even use Linux LiveCDs this way.

    B

    Your experience is exactly why I suggested skipping the BCA stuff. ;)

    That's the plan.

    It can take a while and will do whatever it needs to render W7 bootable, fixing the MBR, installing a new BCD, etc...

    The good news is that it sees W7 to repair.

    I haven't had to use it on my Macs, but it has saved my bacon a few times on my DIY PC.

    B
     
  9. tugger thread starter macrumors regular

    tugger

    Joined:
    Apr 14, 2005
    Location:
    KTLH
    #9
    Well, I was mistaken before when I said I had removed the drive with XP before I booted from the Win7 Install disc. In fact the XP drive was there when the install disc repair function found the WIN7 ("Bootcamp") drive. When I removed the drive with XP the Install disc repair tool could no longer see the WIN7 installation. So I reinserted the XP drive and the installation disk repair tool saw the Windows 7 installation. I selected repair, but it found nothing wrong. So it's not going to create an MBR on the Windows 7 installation because it sees it in the XP installation. [See below image from Disk Management tool]

    Apparently this isn't an uncommon problem. I Googled "mbr wrong disk" and got quite a few hits. Among them was this one explaining how to use bcdboot from the command line to copy the MBR from its existing location to the drive you want it to be on.

    I think I understand how to enter the command to copy the MBR to my WIN7 installation. What I don't understand is where the author says:

    "I ran it, and rebooted. I immediately went into the BIOS and changed the Boot Order so that my 300 GIG C: faster drive (the one I thought I was booting off of all the time) was my startup drive."

    Do I need to perform this step? I think this probably not necessary for my situation, but please correct me if I'm wrong.

    Also, two more questions:

    -What's your best guess about whether doing this will allow the Mac to see the WIN7 installation as bootable?

    -Will bcdboot also remove the MBR from the XP installation so I'm not dealing with dueling MBRs if both Windows disks happen to be in the computer at the same time?

    Thanks again.

    - Jev McKee
     

    Attached Files:

  10. tugger thread starter macrumors regular

    tugger

    Joined:
    Apr 14, 2005
    Location:
    KTLH
    #10
    Problem solved

    I tried bcdboot but couldn't get it to work. Following another user's suggestion I tried the additional step of using the Windows 7 Disk Management tool to set the partition status to Active. This didn't resolve the issue either. Running bcdboot again after this step had no result.

    Someone else suggested I check out EasyBCD, and this worked! On the "BCD Backup/Repair" tab you simply select "Change boot drive," then hit the "Perform Action" button. At the pop-up menu presented you then select the partition you want to boot from. It's really that simple. The procedure creates the required files on your selected Windows installation, and assigns the "System" and "Active" flags to it.

    After this I could remove the disk with XP and the "Windows" selection appeared when holding the Option key at boot. The Windows 7 installation also shows up fine when booting from the WIN7 Installation disc.

    I had one small problem still with the Windows 7 partition not appearing in the Startup Disk System Preference pane. This was a nut-buster to figure out. On a hunch I disabled NTFS-3G for that volume, and everything now works as expected.

    Thanks.

    - Jev McKee
     

    Attached Files:

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