I have been using virtual machine installations of the Windows operating system ever since I made the switch from Windows to Linux when I was attending university (and I have since switched to a Mac OS X setup that has been serving me very well for the past 12 years). I can get most of my daily business done on any OS but I am still in the need of using some tax/finance software that is only available for Windows. Therefore, I have migrated my physical Windows box into a VM a long time ago; I’ve been using Parallels Desktop and VMware Fusion in the past but made the move to VirtualBox about 2 years ago. So far I was running a Windows 7 guest on a OS X host.
Since Microsoft announced their free Windows 10 upgrade policy for existing users, the system has more or less pestering me with “get your copy of Windows 10″ messages. I was curious about trying out the upgrade in a VM before rolling it out to any other family members’ computers (I don’t really enjoy spending endless nights with my mother-in-law’s notebook…).
Unfortunately, the automatic upgrade failed. Well, of course it did. I kind of was expecting to run into trouble.
After performing a requirements check, the Windows 10 Upgrade application was complaining that my computer wasn’t meeting the hardware requirements for Windows 10, in particular the VirtualBox (virtual) graphics adapter which was accused of not being compatible with Windows 10. The VGA driver shipped with and installed by the VirtualBox Guest Additions was (of course) compatible with my current Windows 7 installation but apparently not with Windows 10.
I tried different approaches to force the installation of the graphics adapter driver for Windows 8/10 through the VirtualBox addons but made no progress.
Luckily, the solution was indeed fairly simple: Instead of my first attempt of letting the Windows 10 migration tool download the upgrade files and having it perform the upgrade from within Windows 7, I chose to download the Windows 10 ISO disk image provided by Microsoft. By using the Media Creation Tool within the Windows 7, I was able to obtain the ISO file and transferred it outside to VM to the OS X file system (by mounting a shared folder).
After properly shutting down the VM I then mounted the ISO image to the optical disk drive of the Windows 7 VM and started it. Booting off the Windows 10 installation media, the setup program found the Windows installation on my (virtual) hard drive and gave me the option to perform the upgrade. A few clicks here and there and I was good to let the upgrade procedure begin.
Now it was time for a cup of hot espresso and a short break… The upgrade went flawlessly in the background, while I was able to complete other tasks in the meantime. Some 30 minutes later the virtual machine greeted me with a chime and the shiny new (to me) Windows 10 login screen and I was able to access my migrated user account, including all documents and applications I had previously used.