Why might you be unable to change the console screen resolution on a configured VM?

The reason you might be unable to change the console screen resolution on a configured virtual machine is that the virtual machine's video memory is set too low. Each virtual machine is allocated a certain amount of video memory, which is essential for supporting various display resolutions. If this allocation is insufficient, it can limit the resolutions that the guest operating system can effectively use.

When the video memory is low, the system may not be able to render higher resolutions or may default to lower ones to manage resource constraints. This means users could be unable to increase the display resolution to anything higher than what the available memory can support.

Other factors, while potentially contributing to resolution issues, do not have as direct an impact as the video memory configuration. For instance, if the guest OS is incompatible with the virtual hardware, it may still operate but not offer all resolution options. If the VM is powered off, changes cannot be made until it is up and running. Finally, if the display adapter is not recognized, it might affect functionality, but still, the underlying issue of inadequate video memory would prevent achieving higher resolutions effectively.