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To fix NET Framework 3.5 installation Error 0X800F081F, 0x800F0906 in Windows 10 Windows 8.1, Windows Server 2012 R2 first Download and copy netfx3-onedemand-package.cab file to Windows installation Drive (C: dirve) Then open command prompt as administrator and run command Dism.exe /online /enable-feature /featurename:NetFX3 /source:C:\ /LimitAccess windows101tricks.com/fix-net-framework-3-5-installation-e...