If you are trying to run legacy software or older games on a modern PC, you have likely encountered the prompt: "This application requires .NET Framework 3.5." While Windows 10 and 11 include this feature, it is not installed by default.
If you do have internet access and just want the easiest path: Press Win + R, type optionalfeatures, and hit Enter. How to Download & Install
Options and steps
For Windows 11 (Build 28000 and later), Microsoft has transitioned .NET 3.5 to a standalone deployment . You can download the .NET Framework 3.5 Service Pack 1 (Full Package) directly from the Official Microsoft Download Center Offline DISM Method: You can download the
This method is best if you have no internet access on the target PC. You will need a Windows 10 or 11 ISO file or a bootable USB drive. Microsoft Learn Mount the Media : Right-click your Windows ISO file and select , or insert your Windows installation USB/DVD. Identify the Drive Letter File Explorer and note the drive letter of the mounted media (e.g., Run Command Prompt as Admin : Search for , right-click it, and select Run as administrator Execute the DISM Command : Type the following command, replacing with your actual drive letter, and press Identify the Drive Letter File Explorer and note
This method typically requires an internet connection to download files. However, if your system image was pre-configured with the payload, it might work offline. Microsoft Learn
Replace <DRIVE_LETTER> with the drive letter of your USB/DVD.