Resolving .NET Framework Installation Error 0x800f081f on Windows 8.1

To rectify the .NET Framework installation error 0x800f081f on Windows 8.1, follow these guided steps:

1. Update Windows 8.1: Ensure your system is up-to-date by navigating to Settings > Update & Security > Windows Update and selecting Check for updates.
2. Utilise the .NET Framework Repair Tool: Access Microsoft's .NET Framework Repair Tool to alleviate common setup problems. Obtain and execute the tool from the Microsoft official site.
3. Manually install .NET Framework: Should the previous methods fail, consider a manual installation of .NET Framework. Secure the installer from the Microsoft website and execute it with administrator privileges.
4. Deactivate antivirus programmes: Antivirus software may obstruct the installation. Temporarily disable your antivirus and proceed with installing .NET Framework.
5. Perform a clean boot: Initiating a clean boot might solve underlying software conflicts that impede the installation. Refer to this detailed guide from Microsoft on how to perform a clean boot.