To activate Microsoft Office LTSC Professional Plus 2021 using the Command Prompt (CMD), you must utilize the ospp.vbs script located in the Office installation folder. This method is primarily used for Volume Licensed versions via Key Management Service (KMS) or Multiple Activation Key (MAK). Steps to Activate Office 2021 via CMD Office Activation Command by Omman - GitHub Gist
cscript.Activación por clave de producto (MAK o KMS) — adecuada para licencias por volumen o claves legítimas: activar office ltsc professional plus 2021 con cmd
Successful output: "Product activation successful". To activate Microsoft Office LTSC Professional Plus 2021
Windows + X y selecciona "Símbolo del sistema (Administrador)" o "Windows PowerShell (Administrador)" dependiendo de lo que veas. En Windows 11, puedes simplemente buscar "cmd" y seleccionar "Ejecutar como administrador".