I have a Windows 10 desktop that I run headless. When I plug in a display, it correctly uses that display's native resolution. When I disconnect the display and connect to the computer over VNC, the resolution is locked to 1024x768. There are several places to adjust the resolution (classic Control Panel, new Settings panel, Nvidia control panel) but all fail with various errors along the lines of "settings could not be saved."
Is it possible to change the display resolution to something under than 1024x768 when running headless?