The file Microsoft-windows-netfx3-ondemand-package.cab is the core package used to install .NET Framework 3.5 (which includes .NET 2.0 and 3.0) on modern Windows systems without an internet connection.

• Mismatched Versions: If you are trying to install the .NET 3.5 package from a Windows 10 version 1909 ISO onto a machine running Windows 10 version 21H2, it may fail. Always try to use installation media that matches the exact version of Windows installed on the target machine.
• Corrupt ISO: If the extraction fails, the ISO file might be corrupt. Re-download the media creation tool from Microsoft.
• Missing Language Packs: For some versions of Windows, installing .NET 3.5 requires the corresponding language pack to be installed first. If you are running a non-English system, ensure your base language pack is correctly configured.

: Specifies the location of the files needed to restore the feature. 3. Common Alternatives & Tips .Net Framework 3.5 | O/S Deployment - EduGeek

Note: Ensure the version of the .cab file matches your Windows build version (e.g., use a Windows 10 version 22H2 source for a 22H2 installation) to avoid compatibility errors.