The program window disappears but the program is still running

If the desktop disappears after logging in but the program is still running, it means your windows have been hidden. You can try moving the window back onto your screen using the Windows key + arrow keys. Otherwise, try mousing over the DAS icon in the taskbar, then right click on the window preview and select move, then use the mouse/arrow keys to move the desktop back onto the screen, and resize it by dragging the lower right corner.