There are three variants of the file:
- C:\LOGO.SYS: the "Starting Windows" message, with the Windows logo. The default LOGO.SYS file is also stored in IO.SYS and used by MS-DOS during startup if LOGO.SYS could not be found. The display of the logo can be disabled by adding a
LOGO=0setting in the MS-DOS 7 configuration file MSDOS.SYS.
- C:\WINDOWS\LOGOW.SYS: the "Please wait while Windows is shutting down" message. The Windows logo is shown only in Windows 95 and 98. No error will be shown if the file cannot be found.
- C:\WINDOWS\LOGOS.SYS: the "It is now safe to turn off your computer" message. This message is displayed when Windows has successfully shut down to MS-DOS but is not configured to return to the prompt (COMMAND.COM) again. On systems with proper ACPI support and ATX power supply, the PC may power down instead. If the file cannot be found, the same message is displayed in text mode. No error will be shown if the file cannot be found.
LOGO.SYS is in fact an RGB-encoded bitmap file with an resolution of exactly 320×400 pixels at 256 colors. Windows stretches the image to 534×400 pixels and adds a border to fill the 640x480 video mode while it is visible.
For LOGO.SYS or the equivalent embedded image in IO.SYS, Windows will also animate the image's color information using palette rotation; the image is static, but may have the illusion of movement as colors are changed.
The files may be opened and edited using image editing tools such as MS Paint, and the contents replaced with user-selected pictures.
- Replace the Ugly Startup and Shutdown Screens (archived version)