Microsoft .net Framework 4.8.1 Offline Installer

You can download the official standalone packages directly from Microsoft: Runtime Offline Installer : Best for users who just need to run applications. Developer Pack

You are trying to install on an unsupported OS version (e.g., Windows 7, Windows 8, or old Windows 10 builds like 1507/1511). microsoft .net framework 4.8.1 offline installer

Released as an update to version 4.8, is a highly compatible, in-place update. It includes several key improvements, most notably: You can download the official standalone packages directly