Install .NetFramework 2 & 3.5 from windows source ISO file - OFFLINE

Step 1: Insert Windows 7/8/8.1/10 DVD or mount ISO image. The source of this feature can be found in folder E:\sources\sxs (In this case E: drive letter will be on which Windows 7/8/8.1/10 Media is located).

Windows 7/8/8.1/10 Media folder view

Step 2: Open cmd.exe (Command Promt) with Administrative Privileges.

Step 3: Run the following command

dism /online /enable-feature /featurename:NetFx3 /All /Source:E:\sources\sxs /LimitAccess

and then hit Enter.

Command Prompt shows installation of the feature completed.

Finish: After completing the installation of .NET Framework 3.5 you can see that the feature is enabled as shown in the screenshot below.

Windows features displays .NET 3.5 installed.