Open Notepad
Copy and paste the following into it:
@echo off
Title .NET Framework 3.5 Offline Installer
for %%I in (D E F G H I J K L M N O P Q R S T U V W X Y Z) do if exist "%%I:\sources\install.wim" set setupdrv=%%I
if defined setupdrv (
echo Found drive %setupdrv%
echo Installing .NET Framework 3.5...
Dism /online /enable-feature /featurename:NetFX3 /All /Source:%setupdrv%:\sources\sxs /LimitAccess
echo.
echo .NET Framework 3.5 should be installed
echo.
) else (
echo No installation media found!
echo Insert DVD or USB flash drive and run this file once again.
echo.
)
pause
Save it as as framefx.cmd
Right click framefx.cmd
Click Run as administrator
The file will install .NET Framework 3.5 automatically after finding the drive letter of your Windows 10 installation media.
If media not found insert Win10 Usb or Dvd drive and run as administrator again.
If there is an issue in regards to your install media, download the Windows 10 ISO file then double click it to mount it.