"多目标 .NET Framework 4 和 Visual Studio 2012"

Question

I have installed Visual Studio 2012 Professional on my machine. I don't have Visual Studio 2010 installed, but I want to keep developing my applications using .NET Framework 4, but I don't have this option on my Visual Studio 2012. Look at the image:

I don't know what can I do to fix this problem, because I click on "More Frameworks..." link and try to install the Multi-Targeting for .NET 4.0.3 (installed on my machine), but it does not work. It says that this version of framework is still installed. What can I do to fix this problem?

Obs: I have lots of projects in C# and VB.NET with .NET 4.0, and I need to keep these projects with new projects on .NET 4.0.

Answer 1

I solved the problem doing these tasks:

• Uninstall the Visual Studio 2012
• Uninstall any reference for the .NET Framework 4.0 or 4.5
• Clean the register with a tool like Glary Utilities and restart the computer
• Install the .NET Framework 4.0 and install Microsoft Multi-Targeting for .NET Framework 4.
• Install Visual Studio 2012 again

Answer 2

You fixed your problem, but it's likely that .NET Framework 4 Targeting Pack (not to be confused with the .NET Framework itself) failed to install for some reason. Did you get a warning at the end of the Visual Studio installation? Either way, in the future, a repair install of Visual Studio 2012 should have fixed the problem (Add or Remove Programs -> Microsoft Visual Studio [Edition] 2012 -> Change -> Repair).

Answer 3

I think that your issue is probably some mishap with the installation of .NET Framework. I installed Visual Studio 2012 Beta and have all kind of troubles with compatibility between framework versions. The only remedy was reinstalling Visual Studio, including .NET Framework.

Check out How to: Target a Version of the .NET Framework (MSDN).

Answer 4

创建新项目后，转到其属性（在解决方案资源管理器中选择项目，然后右键单击并选择属性）并选择目标框架！

Answer 5

I'm having a similar problem with Visual Studio 2021 on Windows 10.

I cloned a repository that has some .NET 4.0 projects, and Visual Studio gave me a dialog box recommending I update the target to .NET Framework 4.8 (not an option for me) but also offering to open a browser link to download the .NET Framework 4.0 targeting pack.

The targeting pack doesn't exist at the above mentioned link or in the Visual Studio Installer. There is only a 4.0 runtime, but if I try to install this Windows just says this or a newer version is already installed.

I'll try uninstalling / reinstalling as described by Felipe Oriani above.

There is also a solution described at the link below involving an XML file. https://superuser.com/questions/494553/net-framework-4-0-targeting-pack-does-not-show-in-visual-studio

But since this issue is quite a few years old, if anyone has any new information it would be good to hear.