Microsoft Windows 11 Pro
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Perpetual (Lifetime) License
Download directly from manufacturer's website
For one PC
 
System Requirements for Windows 11:
Processor: 1 GHz or faster with at least 2 cores on a compatible 64-bit processor or SoC
RAM: 4 GB or more
Storage: 64 GB or larger storage device
Graphics Card: DirectX 9 or later with WDDM 1.x driver
Display: 800 x 600 resolution or higher