Microsoft Windows 1.03 for DEC Rainbow
Released in 1987 by Digital Equipment Corporation/Microsoft
For DEC Rainbow running MS-DOS
This version of Windows is specifically for the DEC Rainbow computer.
Important: This software will not run on IBM PC systems or emulators.
Use PKXARC or a similar extraction tool to extract these to a Rainbow compatible disk.
Source:
http://bsdimp.blogspot.com/2017/05/rainbow-100-windows-10-disks-redux.html
https://christopherrivett.co.uk/2018/04/08/windows-1-0-on-the-rainbow/