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How to get 16:9 widescreen in Windows 8 CP using VirtualBox
Note: This is for users running Windows 7

- Power off your VM if it is running.

- From the Start Menu, go to "Accessories" and open "Command Prompt"

- Paste the following command into your prompt:

"C:\Program Files\Oracle\VirtualBox\vboxmanage" setextradata "_put your VM's name here, keep the quotations" CustomVideoMode1 1366x768x32

- Exit out of the command prompt, open VirtualBox, and load up your VM.

- Navigate to the desktop in the Windows 8 VM, right click on the desktop and select "Screen Resolution". The new video mode should be in there. Select it and you're good to go!

Hope this helps!
Vlad P's profile photoDocumentos Compartir's profile photoKai-Uwe M.'s profile photoSam Tomkinson's profile photo
Not entirely sure, let me see if I can find a link. I'd imagine it's pretty similar to what goes on in Win7, but through the terminal instead.
Hey +Michael Reut, try going into the terminal and using "/usr/bin/VBoxManage" as the executable instead of the Windows one I posted. Keep the parameters on the end of it, o' course.

Let me know how it goes. I'm curious!
i updated virtual box and the machine resolution became awful and redid the steps in this page nothing changed (i go to resolution panel)
Works on Solaris 10 too ... now my Windows 8 has the correct resolution.

In my case I also had to "motivate" it to accept my new resolutions by briefly triggering full-screen mode, and only then Windows 8 would abandon the default 1024x768 resolution and scale to the new correct one. Odd ... but it works now. So if anyone runs into the same problems and the changes above don't seem to have any effect: Trigger full-screen mode! That should help ... Afterwards you can go back to windowed mode and Windows 8 should auto-adjust now....
Vlad P
Thanks, worked !
It helped, it worked perfectly for a Windows XP 32-bit version in that very same resolution! Thank you very very much! +1000
worked on windows 10. What it do it only edit the .vbox File on Path C:\Users\YourUser\VirtualBox VMs\Your VM and add the Line
 <ExtraDataItem name="CustomVideoMode1" value="1366x768x32"/>
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