Windows Neptune build 5117

A file, namely, with version number 5.50.5117.1 can be found from Windows Millennium build 2470 to build 3000, but it is unknown whether this Neptune build ever existed.

Some speculate this would've been a Milestone 2 build. It would've been compiled someday after 1999-12-11, meaning it would be one of the last Neptune builds before the Neptune project was canceled in 2000-01.

Whistler bug reporting page
Bug reporting page in Windows Whistler builds 2211.main.000309-1512 and 2223.main.000411-2307 has version number 5.00.00.5117. Bug reports in this version are saved to, suggesting the bug reporting page was ported directly from a Neptune build.