Boot Camp: iMac displays a black screen during installation of Windows 7
When installing Microsoft Windows 7 on an iMac (27-inch, Late 2009) and iMac (21.5-inch, Mid 2010) using Boot Camp, a black screen may appear. This can happen because the Windows 7 installer does not include the necessary graphics or Bluetooth drivers for your Mac.
Follow the steps below to download the necessary drivers and install Windows 7 on your iMac:
Note: If you are upgrading from Windows Vista, you'll need to use the Apple_Win7_Upgrade_Utility before starting an upgrade install. This is not required for a clean installation of Windows 7.
Go to the bottom of the Software License Agreement for Boot Camp and click "Accept and download" to agree to the license.
The files are contained in a .zip file. Double-click it to expand it.
Connect your USB storage device or SD card.
Note: Your USB storage device must be connected to the back of the iMac directly and not to a keyboard or other non-high-powered HUB.
If the USB device or SD card has not been formatted as MS-DOS (FAT), or if you're not sure, follow steps A through N immediately below; otherwise go to step 5.
Important: These steps will erase the contents of the USB storage device or SD card; back up any important files that are on it to a different disk.
Choose Go > Utilities.
Open Disk Utility.
Select the USB drive in the left side of the Disk Utility window.
Click the Partitions tab.
Choose the number of partitions from the Volume Scheme menu. If you can’t choose the number of partitions, you may be trying to partition your startup disk.
Click Options.
Click "Master Boot Record."
Click OK.
Click the Format tab.
Select MS-DOS (FAT).
Name the disk MBRFAT.
Click Apply.
Click Partition.
When the process is complete, quit Disk Utility.
Drag "Drivers" and "AutoUnattend.xml" from the iMac_Late_2009_2010_ Win7_Drivers folder, which was expanded in step 2, to the icon of the USB or SD card device to copy the files to it. Do not copy them to any subfolders.
Start the Boot Camp Assistant.
Select a partition size and click Partition.
After partitioning has completed, click "Start the installation" and insert your Windows 7 install DVD. Your computer will restart.
Follow the onscreen Windows install instructions. If this is a new installation, remember to use the Windows installer to format the BOOTCAMP partition. You'll need to click on Drive Options (Advanced) to see a Format selection.
Your computer will restart several times during the installation process. The screen may go black for several minutes while the Windows installer locates the drivers on your USB storage device. You should not turn off your computer during this process.
A screen should eventually appear asking you to establish a user account in Windows 7.
If the screen remains black after several minutes, power it off (hold the power button for several seconds), then go back to step 4. Ensure that your USB device or SD card is formatted as Master Boot Record, FAT, and that AutoUnattend.xml and Drivers are on the root level of the directory.
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