Bootcamp troubles - CDBOOT: Couldn't find BOOTMGR

Discussion in 'iMac' started by Buskins, Dec 21, 2012.

  1. Buskins macrumors member

    Feb 14, 2012
    Hi Interwebs!

    My 27" arrived half an hour ago (whoopee) I figured I'd get the boring installs out the way first and am now on bootcamp, but I have run into a slight snag.

    FYI I got the USB superdrive.

    Process so far:

    Opened Bootcamp Assistant. Of the 3 options chose 2 & 3 (i.e. I didn't chose to burn whatever it was to a thumbdrive or disc ... not sur eI own any blank discs and I have no thumb drive)

    Bootcamp Assistant (BA) made its windows support folder on an external harddrive of mine, then I set the partition size and inserted the Windows 7 disc into the superdrive.

    The iMac restarted, and I am now on a black screen with :

    CDBOOT: Couldn't find BOOTMGR

    Is this a result of not having checked option 1? Must I burn something to something... Last machine it worked without the option 1 checked, so I am wondering if this is a result of no internal CD drive - and the superdrive doesn't perform the function of allowing the mac to see the windows disc in this instance.

    Help would be appreciated. Also, any way I can get off this screen without holding down the power button? I really don't want my first forced restart to be within the first hour of the machine being here. (Windows, eh.)

    Cheers for any and all help

  2. Buskins thread starter macrumors member

    Feb 14, 2012
    Update. on phone with tech support who dont have a clue lol. you're my only hope.
  3. Buskins thread starter macrumors member

    Feb 14, 2012
    Update II

    Tech support had me remove the partition and start again, this time removing the usb superdrive (after bootcamp used it obviously)

    When the mac restarted i got o the black screen again, but a new message.

    No bootable device -- insert boot disk and press any key,

    re-insetting the usb superdrive and pressing any key - nothing happens.
  4. mushroomtip macrumors 6502


    Oct 27, 2012
  5. iWaiting macrumors regular

    Dec 10, 2012
    its the usb super drive thats the rouge here

    they do not support a windows boot dvd that why BC lets you copy the windows dvd to a usb stick as a iso to get it to boot

    why do you think Apple gave you the option ? out of the goodness of there heart:eek:
  6. Buskins thread starter macrumors member

    Feb 14, 2012
    I thought as many people may think when given options - that those options are there to make things easier if you chose to go that route. I didn't know that the CD drive I bought as the iMac doesn't have a CD drive will not work for this particular operation.

    I am hesitant to put the windows on a thumbdrive now though as I am reading through that link and it seems even that will inevitably wind up with it not working. I don't want to force-shut down my machine any more today. Apple made me do it 5 times - which is more in this first hour than 4 years of my other machine lol...

    Damn bloody windows.
  7. iWaiting macrumors regular

    Dec 10, 2012

    you said it :D
  8. RicWeb macrumors newbie

    Dec 6, 2012
    Cheshire, UK
    I had the same problem with my Mac mini. Create an image of your windows DVD using disk manager then select option 1 to burn it to a USB flash drive. It worked perfectly for me. ( make sure the DVD image is renamed to .iso).
  9. Buskins thread starter macrumors member

    Feb 14, 2012
    The only word I understood there was thumbdrive...

    Speaking to apple tech he said the thumbdrive needs to be formatted at FAT32 - but then he said MBR -

    As the tech guy mentioned I go into disk utility, select new image - the WHERE is the thumbdrive, the SAVE AS - is that what you mean .iso? So it'll be called GRMCHPXFRER_EN_DVD.iso (GRMCHPXFRER_EN_DVD is what is there by default).

    Image format compressed? Encryption none?
  10. Buskins thread starter macrumors member

    Feb 14, 2012
    Tech Support called back - he had done some research.

    He suggested downloading the version of windows I wanted from

    Scroll down and you'll see it (Windows 7 Home Premium SP1-U ISO)

    He mentioned that it is already an ISO so it can just be put on a thumbdrive formatted as MBR and then when the Mac reboots itself after partitioning the drive I can hold down alt and boot into the thumbdrive windows. The Windows is a trial, but he said I can just then put in my validation key and it'll become the full version.

  11. auwkeung macrumors member

    Apr 8, 2008
    I had exactly the same problem, and I am using a third party ext dvd drive

    I ended up giving in and just use VMWare for time being

    Any successful solution would be welcomed
  12. Operationlvy macrumors newbie

    Nov 29, 2012
    San Francisco, CA
    so you need usb

    So installing Windows on Boot Camp partition will not work with an external dvd drive? You have to use a USB stick that is formatted as MBR?

    I'm gonna set mine up this weekend and it'd be nice to get some confirmation on this. Anybody get Windows installed via external dvd drive?
  13. SBruv macrumors 6502

    Sep 25, 2008
    I've installed Windows 7 via Boot Camp using a USB Superdrive in my 27" Fusion Drive iMac. Went totally bad the first time (like in the thread mentioned above), but flawlessly the second.

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