Windows NT 3.5x/3.50.854

Windows NT 3.5 build 854 is a build of Windows NT 3.5, leaked on BetaArchive by member Darkstar on May 14th 2010. Although the build identifies itself as Windows NT 3.50, it's unclear part of which project it is (NT 3.5, NT 3.51, "Cairo" or NT 4.0), due to its build number and inclusion of OFS.

NT 3.50's RTM build number is 807 and 3.51's is 1057, so in that case it would be either a post-RTM of 3.5 or an early 3.51 build. Because it includes OFS, it could also be a build of Microsoft's canceled project "Cairo" (the codename of which was later re-used for NT 4.0), as OFS was planned to launch in Cairo. Lastly, it could be a very early build of NT 4.0, which was later developed instead of the original Cairo.

This build requires the user to apply the "Pentium 2 patch" prior to installation just like on NT 3.1 and 3.5 builds. Also included is an early version of NewShell, which can be installed later on, but it can cause the build to crash.