And it should work perfectly fine, if you can live with a low-resolution display. On start-up, my Windows 10TP guest machine was using the pre-supplied Microsoft base display driver, which, on my x86 host, would only give me 1024 by 768 in 4:3 ratio. How very 1998.
So naturally, you want to install the VirtualBox Guest Additions. Unfortunately, running the Guest Additions installer crashed out at the graphics driver stage every time.
The first item of advice I found stated:
“If you try installing the guest additions without 3D acceleration first and enable it afterwards, you have to reset/reinstall W10, otherwise the installation routine will be broken because of the first crash and it will not work.”
That’s actually wrong. Early on, I also made the mistake of attempting to install the Guest Additions without having 3D acceleration enabled, and tried to rectify that by running
then rebooting, then reinstalling Guest Additions. Live, die, repeat: you need something else to kill the space octopus.
Sifting through contradictory advice from various forum posts I hit a combination of actions that finally gave me a full screen Windows 10 desktop in 16:9 wide-screen.
Firstly, shut down the Windows 10TP guest; enable 3D in display settings, increase the graphics memory to 256mb; then restart the guest.
Second, the Guest Additions installer has a compatibility issue with the early Windows 10 Technical Preview builds but there is a workaround to install it successfully.
- When starting the installer, change the compatibility mode to Windows 8 then execute the file.
- Right click on the corresponding .exe file ( 32bit or 64bit), go to Properties and under Compatibility tab, select Windows 8 then select Apply.
If that still doesn’t give you a workable display, you may have to work harder to get the best compatible driver.
- Mount the Guest Additions CD
- Open a terminal and change directory to the Guest additions CD
- Next run
VBoxWindowsAdditions-amd-x64 /extract /D=C:\Drivers
- where C:\Drivers can be any folder on your guest machine to store the driver files.
This will extract the drivers manually to the guest hard drive. You can then choose from Windows 7, Windows 8 and Windows WDDM which is the VirtualBox video drivers for 7/Vista; it’s not great for performance but it can give you a full width Windows desktop.
- To change the driver, right-click the desktop, choose Screen Resolution, then Advanced settings, Properties.
- In the Properties window, select Update Driver, then choose the folder location to browse for a new driver file. You will find you have a choice of VBoxVideo, VBoxVideoW8 and VBoxVideoWDDM.
- To adjust the resolution, right-click the desktop, choose Screen Resolution, then Advanced settings, Properties.
Choosing the WDDM didn’t at first appear to work; it needed a restart (it is Windows after all), after which it gave me a sensible 1366 x 768 resolution in full screen mode. AJS