The D3D9 device could not be created. This may happen if the desktop is locked
More advanced games are quite sensitive to screen resolution, by the way, if you play them through an external game launcher like Steam. I saw conflicts with the screen resolution, which completely obscured the screen or at least stopped the game. Similarly, a known problem with screen conflict resolution is when players get the error:
The D3D9 device could not be created. This can happen when the desktop is locked
.
One possible reason for the error could be that the resolution of the game differs from the current screen configuration, although there may be other reasons for the problem.