Jan 25, 2015 · How to Enable full Screen On Virtual Box any windows. - Duration: 3:41. PcMobiTech 81,237 views. 3:41. Building a PC... using only Wish.com - Duration: 22:05. Linus Tech Tips Recommended for you.
Since upgrade to VirtualBox 5.1.26 r117224 (from 5.1.24 r117012), the display resolution is not evaluated properly. At startup the VM display resolution is wrong in fullscreen mode (1920x1080 instead of 1340x1440 on the host). There is no way to set it manually in Windows display properties settings. The maximum proposed resolution is 1920x1080. I had this issue "Auto-resize Guest Display" greyed out / disabled on a guest Windows 10 over a Ubuntu 16.04 host, I've sorted it out after long search with the simple hint (found in LinuxQuestions org): enable the VirtualBox Guest Additions Tray Applications in the Task Manager / Startup tab.