Windows NT 3.1 build 127.1
|Build of Windows NT 3.1|
Windows NT 3.1 build 127.1 is a very early build of Windows NT 3.1. It was mentioned in an internal document from the Windows NT 4.0 source code, which was leaked in 2004. The document suggests this build already had a working GUI and was compiled before 1991-05-01.