Mount the Windows 10 or Windows 8.1 iso file

Locate (D – Mounted ISO path) D:\sources\,  copy the contents to c:\ drive of the computer. (I used different computer to transfer)

I did in c:\download\sxs

Run as administrator – Command Prompt and run the following command,

Dism.exe /online /enable-feature /featurename:NetFX3 /source:C:\Download\sxs /LimitAccess

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