I am running above application in Windows 10- 64 bit. I have previously run same set-up on Windows Vista with VM Workstation 7 with no problem. Using Workstation 7, the DOS Window takes up about 2/3rds of screen in height and about 3/4 in width making a very usable work space. In Workstation 12 on Windows 10, I cannot get the DOS Window any larger than 1/3rd - 1/2 screen height and 1/2 of screen width making a window too small for working effectively. I have tried all different settings on properties tab of the DOS.exe icon and various screen resolutions on the guest and nothing changes. I know this is a very elementary type problem, but it vexes me. If anyone has a solution or suggestion, it will be greatly appreciated. Thank you.