.NET Framework 3.5: Features, Installation & Uses
.NET Framework 3.5 is a critical component of Microsoft’s .NET ecosystem, providing a runtime environment for Windows applications. As an enhanced version of .NET 2.0, it introduced Language Integrated Query (LINQ), Windows Communication Foundation (WCF), and better support for ASP.NET AJAX.
In this guide, you’ll learn:
1. What .NET 3.5 is and why it’s important
2. How to install .NET Framework 3.5 on Windows
3. Key features and compatibility
4. Common applications using .NET
What is .NET Framework 3.5?
.NET Framework 3.5 is an improvement over .NET 2.0, adding features like:
- Language Integrated Query (LINQ) – Enables database-like queries in C# and VB.NET.
- Windows Communication Foundation (WCF) – Simplifies building networked applications.
- Windows Presentation Foundation (WPF) – Enhances UI development.
- ASP.NET AJAX Support – Improves web interactivity and performance.
Why is .NET 3.5 Still Important?
- Legacy Support: Many enterprise apps still rely on .NET 3.5.
- Windows Compatibility: Works on Windows 7, 8, 10, and some server versions.
- Backward Compatibility: Supports older .NET applications without modifications.
How to Install .NET Framework 3.5 on Windows
Follow these steps to install .NET 3.5 on Windows 10/11:
Method 1: Install via Windows Features
- Open Control Panel → Click Programs → Turn Windows features on or off.
- Check the box “.NET Framework 3.5 (includes .NET 2.0 and 3.0)”.
- Click OK and wait for the installation to complete.
Method 2: Install via Command Prompt (Offline)
If you face issues, use this command:
Applications Built Using .NET 3.5
Many legacy applications were developed using .NET 3.5, including:
- Business Applications – ERP, CRM, and enterprise tools.
- Desktop Software – Windows-based utilities and tools.
- Web Applications – ASP.NET-based web portals with AJAX.
Learn more about ASP.NET and Web Development.
.NET 3.5 vs. Modern .NET Versions
| Feature | .NET 3.5 | .NET 6+ (Modern) |
|---|---|---|
| Release Year | 2007 | 2021+ |
| Performance | Moderate | High |
| Cross-Platform | Windows Only | Windows, Linux, macOS |
| Best For | Legacy Apps | Cloud & Web Apps |
Conclusion
.NET Framework 3.5 remains relevant for legacy applications and enterprise systems. Although newer versions like .NET 6 and .NET 8 offer better performance, many companies still rely on .NET 3.5 for stability and compatibility.
Explore More:
Microsoft .NET Documentation
.NET Migration Guide