Is there any way to install Windows 10 on unsupported Mac (iMac mid 2011) without resort to various tricks with virtual machines?
A different user recently posted a similar question on superuser. Since my answer was accepted as correct, I will repost it below.
The Basic steps to install 64 bit Windows 10 are as follows. I assume here that your current configuration is the default "Out of the Box" OS X installation.
- Download the correct Boot Camp Support Software for your Mac. Transfer these files to a FAT formatted flash drive. For your Mac, use the same software as for a 64 bit Windows 7 installation. These files can be found at Boot Camp Support Software 5.1.5621
- Use the Disk Utility to reduce the size of your OS X partition. In the empty space, create a FAT formatted partition with the label BOOTCAMP.
- Burn the Windows 10 iso file to a DVD. You can use the Disk Utility to do this. I always use a RW DVD. This takes longer to burn, but is reusable.
- Restart the Mac with the DVD in the optical drive. Hold down the alt/option key and select the DVD icon with the label Windows.
- Install Windows to the Boot Camp partition. You will have to tell the installer to reformat this partition as NTFS. DO NOT CHANGE THE PARTITIONING DURING THE INSTALLATION PROCESS.
- At some point during the installation, the computer will reboot. When it does, it will boot to OS X. This is to be expected. Go to System Preferences and instruct OS X to boot back to Windows. The installation process will continue.
- After the Windows installation has completed, install the Boot Camp Support software stored on the flash drive. To accomplish this, you will have to right click on the icon and select Compatibility Mode.
I do not consider the process to be that difficult. The most challenging step is creating the FAT formatted partition labeled BOOTCAMP. If something goes wrong, you are in danger of loosing data on your OS X partition.
I was prepared to follow the instructions above, but noticed Boot Camp clearly said "Install Windows 7 or later version". So I tried it and everything worked perfectly.
I installed Windows 10.1 on a mid 2011 iMac running El Capitan, using Boot Camp. The only setback was having to burn the Windows ISO to a DVD because it wouldn't let me install from a USB.
I wonder if they updated Boot Camp Assistant since this question was asked.
I have an 27' Imac 2011, which according to Apple is not supported for Windows 10 install.
I just walked through the steps of Bootcamp 6.0.1, downloaded the Bootcamp support files, created the Windows partition in Bootcamp, inserted a DVD of the W10 x64 ISO that I downloaded from MS and followed the procedures.
The only problem I encountered (eventhough I was prepared for more..) was that I had to get a USB wired keyboard and mouse during the installation steps. However the install as such went smooth and when finalized the Bootcamp support drivers loaded nicely. I had to pair my Apple keyboard with the system. After that everything including sound, Bluetooth, graphics and what not worked like a charm.
Since after build 1511 of W10 you don't have to upgrade from 7 or 8.1 to get a free upgrade, you can do a clean install instead and register with a valid 7, 8 or 8.1 license key, for me that worked great.
So when Apple states that my Imac 2011 is not supported for W10, I guess it's currently more of a statement than a fact. I guess they mean that they don't put any further additional efforts into keeping it compatible onwards whenever MS decides to change W10 system logic.
However since W10 is really a polished W8.1, with basically the same "under the hood" logic, any Apple Bootcamp supported Mac up to W8.1 Mac's (like my Imac 2011) is perhaps likely to support also W10, even if Apple doesen't want to state that.