This file contains a 320 horizontal by 400 vertical pixels by 256 color bitmap which is shown while Windows is starting up. The original screen shows the Windows 95 logo on a cloud background and the animated bar at the bottom.
You can prevent the display of the startup screen by setting the logo parameter in the Options section of the MSDOS.SYS file to
[Options]
Logo=0
You can also replace the startup screen by a new bitmap. This bitmap has to have the same 320 by 400 by 256 colors dimensions. Windows stretches the bitmap horizontally to twice its width, while keeping the vertical scale unchanged.
The standard logo screen has a color bar across the bottom that appears to move. This animation is produced by cycling the colors assigned to the last 20 entries in the 256 color palette. If the bitmap is changed and then saved, then the animation disappears. To restore the animation, load LOGO.SYS into Debug and enter the following commands at the prompt:
E CS:132 EC
W
Q
You can create a full screen animation by expanding the areas that are painted with these last 20 colors. Start by loading the existing logo bitmap in Paint or any other bitmap editing tool. Erase everything except the animated color bar at the bottom. Use the dropper tool in Paint to pick up the color from a rectangular section of the color bar. Then paint something else on the screen with that color. All the objects painted with that color will change color along with the animated color bar.
See LOGOS.SYS for the bitmap notifying the user that it is safe to turn off the computer. See LOGOW.SYS for the bitmap notifying the user that Windows is in the process of shutting down the computer.