Dual Boot Mac OS X / Windows 7

Dual Boot Mac OS X & Windows 7

    For those of you who want to degrade their beautiful hardware with Microsoft, here is an easy way to dual boot Mac OS X and Windows 7. I will go over how to install it and configuring a working bootloader. It is important to understand that the computer world is not a perfect one, and data loss is always possible. Backing up your data is always a good practice. You can use Time Machine on your Mac, its a very nice and cool tool.
  • What I am assuming:
  1. You are trying to dual boot on a custom made PC running Mac (a Hackintosh). If you have a real Mac, you don't need this, you can use Boot Camp.
  2. You already have an exclusive partition you mean to use for Windows 7. If not you will need to resize your harddrive and create a partition for Windows 7 (I can make a guide on how to resize partitions if requested).
  3. You have the ability to type some things in a command line without it ending in calling the fire department.
  4. You are using Legitimate Copies of both OSs.
  • What you will need:
  1. Mac OS X DVD.
  2. Windows 7 DVD.
  3. A USB drive at least 2 MB in size (formatted FAT32). Make sure to note the name of your USB drive.
The procedure:
   1. First of all you will need to download these 2 files. I have provided links. Once downloaded, unzip files (if need be), and copy them to your USB stick then leave the USB drive connected:
   2. Insert your Mac OS X DVD and reboot your machine. Boot into Mac OS X installer (the DVD). Once your in, open "Terminal". Then follow below:

  • First of all we will unmount the OS X partition that was auto-mounted on boot. Type in code without the "#" sign.

  • #  umount /Volumes/NameOfYourOSXpartition
Note: For NameOfYourOSXPartition, use the name that you put for your Mac OS X partition not what I wrote.
    • Next, we will use the gptsync program you downloaded on your USB drive to modify our MBR table so Windows 7 will install on a GUID partition table. Type in each line of code individually and without the "#" sign.

    • #  cd /Volumes/NameOfYourUSBDrive
      #  ./gptsync /dev/disk0   (Choose "Y" when it asks if you are ready to modify)
    Note: Again, for NameOfYourUSBDrive, use the name you assigned your USB drive I asked you to note earlier.

    • Once that is done, quit "Terminal" and reboot your machine, swapping the Mac OS X DVD with the Windows 7 one.
       3. Now that you have the Windows 7 DVD in, we will install Windows 7.

    •  Boot into the Windows 7 installer and click "Advanced" when you get to that step. Choose the partition you assigned for Windows 7 and choose "Format" (see note below). Then proceed with installation as normal.
    Note: If you are unable to select "Format" then try "Delete" partition, then create a new partition from the free space.
       4. After installation is complete it will automatically boot into Windows 7, not Mac OS X. Don't start freaking out... it's O.K. What happens is Windows 7 will install and will install its own bootloader overriding the one you installed for Mac OS X. Windows 7 bootloader does not recognize OS X, so it will not even ask you which OS you want to boot. Now we will install our own bootloader that will recognize both OSs and give us a choice every time we want to boot the machine. Which is what we're looking for. This is the second file I asked you to download, EasyBCD.

    • When you boot into Windows 7 and you are up and running open your USB drive and double click the EasyBCD .exe file you downloaded and install then launch it.
    • Once EasyBCD is launched click "Add New Entry" from the left pane.
    • Click "Mac" from top section. Rename your Mac entry to whatever you want. This is the name of the Mac OS X choice that will show up when you first boot the machine. Then select "MBR" from the "Mode" drop down menu, I wasn't able to get it to work with "EFI (Default)".Then click "Add Entry".
    • Click "Edit Boot Menu" from the left pane. Select the OS you would like it to boot by default after the timeout duration is over ( You would disgrace yourself not selecting Mac, but hey...whatever works for you ;) Change the "Timeout Options" to your liking. Also if you want you can change the order in which the options appear on the bootloader by selecting the OS from the box and clicking Up or Down.
    • Click "Save Settings" and Reboot!
    You are done! On your next reboot, and every boot after that, you will get a black screen asking you which OS you would like to boot. And if you don't select, it will boot the default OS you assigned after the timeout period is over.

    Leave comments if you have any questions or email me (tipsotto@gmail.com).
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    1. this procedure does n seem to be working...
      when i tried unmounting the drive it says no file or directory
      so i went about unmounting the drive from the disk utilities but still when i come to the usb step it says the same..... no file or directory

      how do i go about doing the installation...
      i have a single 1TB HDD... i installed SL 10.6.0 first n updated to 10.6.4.....
      by the way i installed using iboot and not kakewalk since the disc was not recognized....
      how do i install the win7 into the system now......

    2. Could you please email me at tipsotto@gmail.com. It will make it easier for me to help you since this issue has the POTENTIAL of taking a whole page of comments. :) Hopefully we will try to resolve this. It shouldn't be too hard.

      If anyone else is having this issue please let me know, we can storm through it or I can write an alternative way of doing this using something like a Ubuntu Live CD to do the MBR syncing.

    3. I am on to the Windows installation now did have a few problems along the way though, the unmount command as above didn't seem to work for me, I used disk utility instead. Got a few 'no file or directory' messages on the USB step as well but this was simply because of miss typing the command lines (watch out for the spaces after cd on first line and gptsync on second).

      The gptsync command did not complete on first attempt returning an error message, it worked second time when I unmounted both partitions prior to the terminal commands.

      When you reboot from windows CD make sure you press a key quickly when 'boot from cd/dvd' message is shown I was too slow the first couple of times and thought there was a problem as it jumped back into OSX bootloader.

      Windows nearly done now....even the installation is slow and painful compared to OSX! Will report back when I know if it has succeeded

      Once again thanks TipsOtto brilliant tutorials

    4. All done EasyBCD works a treat

    5. @Rich
      Thanks Rich for your feedback. I appreciate it. gptsync can be weird. I'm glad you figured it out. Yes, your required to unmount all partitions that might have auto-mounted.
      Thanks again for your feedback :)

    6. I have trouble with going back to Mac OS X. I do what you recommended, but it doesn´t start up the Mac OS X. I tried the EFI setting, then it simply doesn´t start and it goes back to the menu where I can choose between windows and mac OS. If I use MBR mode, it go to a black screen with the message chain booting error. What I was thinking of doing is to just delate windows from the booting menu, but I am afraid that then nothing will start. Please advice! Thanks

    7. hi...Im student from Informatics engineering nice article,
      thanks for sharing :)

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