Sometimes, a corrupted .NET Framework installation can block a new one. You can use Microsoft's official tools to repair this:
https://dotnet.microsoft.com/download/dotnet-framework/net48 net framework 4.8 windows 10 64 bit
Corrupt Windows Component Store. Fix:
The hardware requirements for .NET Framework 4.8 are minimal and should be met by virtually any system running Windows 10 64-bit: Sometimes, a corrupted
Application deployment models: On Windows 10, developers commonly deploy .NET Framework 4.8 apps via MSI, ClickOnce, MSIX, or packaging in setup programs. With MSIX and modern packaging, Windows 10 supports modern distribution while preserving .NET Framework compatibility. With MSIX and modern packaging, Windows 10 supports
.NET Framework 4.8 is included as a native system component. You do not need to install it manually.
Temporarily disable your third-party antivirus software or firewall. Run the installer again, or use the Deployment Image Servicing and Management (DISM) tool via the command prompt to repair your system image: DISM.exe /Online /Cleanup-image /Restorehealth Use code with caution. The Microsoft .NET Framework Repair Tool