10 — Winntx 62 Windows

Older 32-bit components (like .ocx or .dll files) from the NT 6.2 era can often still be registered in Windows 10 using the regsvr32 command in the SysWOW64 folder. Summary of Key Versions Windows Version Internal Kernel Version Key Characteristic Refined the Vista (6.0) architecture. Windows 8 NT 6.2 Introduced the Start Screen and touch UI. Windows 8.1 Improved UI and personalization. Windows 10 NT 10.0 (formerly 6.4) Unified platform for all devices. Installation problem - Microsoft Q&A

: Sometimes the "stuck" progress bar is actually processing thousands of small files in the background. Give it at least 2–3 hours before forcing a restart. winntx 62 windows 10

So — it’s Windows 8.