Open File Explorer and navigate to: C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\ Look for a folder named or v4.5.2 .
Microsoft has updated its distribution infrastructure over time. To find the official downloads, navigate to the centralized .NET download repository:
Because .NET Framework 4.x updates are "in-place," installing a newer runtime (like .NET 4.8) sometimes blocks older runtime installers. However, you can still install older targeting packs . Ensure you are downloading the , not the standalone runtime installer. 2. Missing in Modern Visual Studio (2022 and Newer)
Why developers need it
: Offers cross-platform development across Windows, Linux, and macOS.
If you are using Visual Studio 2013, 2015, or later, and try to open an older project targeting .NET 4.5, you may encounter an error stating,
If you use modern versions of Visual Studio (such as Visual Studio 2019 or 2022), you do not need to download standalone installers. You can install targeting packs directly through the Visual Studio Installer. Open the on your computer.
Read through the Microsoft Software License Terms, check the I agree box, and click Install .
Check the DWORD value to determine the specific sub-version. ⚠️ Important Security Note
Error MSB3644: The reference assemblies for .NETFramework,Version=v4.5 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application
.NET Framework 4.5 Developer Pack (which includes the Multi-Targeting Pack) is a critical resource for software developers who need to build or maintain applications targeting the .NET Framework 4.5 using Visual Studio. Essential Download Links While .NET Framework 4.5 has reached its End of Life
The contains only the runtime components—enough to run an application, but not enough to build one. The Developer Pack also includes language packs that provide IntelliSense files for displaying help information when building applications.
The .NET Framework 4.5 Developer Pack supports the following Windows versions:
: Up to 4.5 GB of available space on your hard drive (depending on system architecture). Step-by-Step Installation Guide