Windows Neptune build 5022.1

29 files with version number 5.50.5022.1 and product name "Microsoft(R) Neptune (TM) Operating System" are found in Windows Millennium Developer Release (Build 2332.2), but it is unknown whether this Neptune build ever existed. If the build is real, it was probably one of the first Neptune builds. Judging by the file dates, it would be compiled someday in the first half of June '99 (before 13th June), which is also when the Antitrust docs start mentioning Neptune more frequently.