Resolving Installation Error 0x800f0831 for .NET Framework 3.5 on Windows Server 2019

To address the installation error code 0x800f0831 for .NET Framework 3.5 in Windows Server 2019, follow these steps:

1. Verify the installation of .NET Framework 3.5: Navigate to the Control Panel, select Programs and Features, and check if .NET Framework 3.5 is listed. If present, no further installation is required.
2. Employ the DISM tool: Launch the Command Prompt with administrative privileges and execute the command: DISM /Online /Enable-Feature /FeatureName:NetFx3 /All /LimitAccess /Source:D:\sources\sxs. Ensure to adjust 'D:' to the drive letter where your Windows Server 2019 installation media resides. This will allow the installation of .NET Framework 3.5 directly from the media.
3. Run the Windows Update Troubleshooter: Access the Settings menu, select Update & Security, navigate to Troubleshoot, and choose Windows Update. Execute the troubleshooter and comply with the provided steps to resolve any potential issues.
4. Check for system updates: Within the Settings menu, head to Update & Security, and select Check for updates. Installing new updates may occasionally rectify problems associated with .NET Framework 3.5 installation.
5. Utilize the .NET Framework Repair Tool: Download and run the .NET Framework Repair Tool available on Microsoft's official website to address common issues encountered during the installation process.