Here is how to install NetFramework 3.5 offline in windows 10 & Windows 8.1 / 8 .

  1. Open Start Menu and press cmd , Now press Ctrl+Shift+Enter , This opens administrative command prompt.
  2. Now copy the below code and replace The drive letter source for windows 10 setup files for example here is E:Dism /online /enable-feature /featurename:NetFX3 /All /Source:E:sourcessxs /LimitAccessas
    windows 10 supports copy paste in command prompt , So in command prompt windows just paste it by Ctrl+V  , changing above mentioned source, press ENTER , This takes few minutes
  3. That’s Done


I Found a interesting script that automatically finds mounted Images and Installs Net-framework 3.5

Copy and save this as .bat file and right click and run as administrator


Source of script- Winaero