Hello,
The M365 A3 license does not provide the right to activate Windows 11 Enterprise. M365 A3 licenses focus on providing access to Microsoft Office applications and services.
To activate Windows 11 Enterprise, you typically need a Windows 10 or Windows 11 Enterprise Volume Licensing agreement or an appropriate subscription that includes the right to use Windows Enterprise, such as Microsoft 365 E3/E5.
https://www.microsoft.com/en-us/microsoft-365/windows/windows-11-enterprise
Best Regards,
Hania Lian
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