Net Framework 45 Developer Pack Link -

Cause: You already have a newer version (e.g., 4.7 or 4.8). The Developer Pack will refuse to install because the runtime is superseded. Fix: You don’t need the full Developer Pack. Instead, install the .NET Framework 4.5 Targeting Pack from the Visual Studio Installer (Individual Components → SDKs, libraries, and frameworks → “.NET Framework 4.5 targeting pack”).

The actual installation takes 1–3 minutes. No user input is needed. net framework 45 developer pack link

https://www.microsoft.com/en-us/download/details.aspx?id=42637

(Note: Microsoft may redirect to a newer page, but the GUID 42637 is permanent for .NET 4.5.1 and 4.5.2. For pure .NET 4.5, see the historical note below.) Cause: You already have a newer version (e