Microsoft Cairo build 1175

Microsoft Cairo build 1175.1 is a late build of Microsoft Cairo, based on the core of Windows NT 4.0 build 1175.1. This build was leaked by The Distractor on BetaArchive on 2017-03-17.

It has some differences from the regular SUR build:
 * Cairo OFS (Object File System) support
 * Cairo Domains support
 * Updated Setup wizard
 * Updated login screen
 * Additional Cairo components

Virtualization
This build can be installed with PCem, 86Box, VirtualBox, or VMware. VM compatibility should target Windows NT 4.0. Installing the build with NTFS or FAT is recommended, as booting from OFS will cause it to hang. DM domain should also be installed, otherwise it will be nearly impossible to log in. Logging in uses the same username and password used during setup.

When you log in, the first time you load, you must use Ctrl+Alt+Del and log off, since each time Explorer first loads, it will hang loading. You can then log in again normally. Most functions in Explorer such as changing the background can cause Explorer to hang and force you to log out and back in again to regain control.

More info on how to install here.