1. To install .NET Framework 3.5 in Windows 10, do the following:
  2. Insert your Windows 10 DVD, or double click its ISO image, or insert your bootable flash drive with Windows 10, depending on what you have.
  3. Open 'This PC' in File Explorer and note the drive letter of the installation media you have inserted. In my case it is disk D:
  4. Now open an elevated command prompt and type the following command but replace D: with your drive letter for Windows 10 installation media:
  • Dism /online /enable-feature /featurename:NetFX3 /All /Source:D:\sources\sxs /LimitAccess 
  • You are done! This will install .NET framework 3.5 in Windows 10.