When you run the web or offline installer for the .NET Framework 4.5 or later versions,
you might encounter an issue that prevents or blocks the installation of the .NET Framework.
The following table lists possible blocking issues and provides links to troubleshooting information.
In Windows 8 and above, the .NET Framework is an operating system component and cannot be independently uninstalled.
Updates to the .NET Framework appear in the Installed Updates tab of the Control Panel Programs and Features app.
For operating systems on which the .NET Framework is not preinstalled,
the .NET Framework appears in the Uninstall or change a program tab (or the Add/Remove programs tab) of the Program and Features app in Control Panel.
For information on the Windows versions on which the .NET Framework is preinstalled, see System Requirements.
Important
Because the 4.x versions of the .NET Framework are in-place updates,
you cannot install an earlier version of the .NET Framework 4.x on a system that already has a later version installed.
For example, on a system with Windows 10 Fall Creators Update, you cannot install the .NET Framework 4.6.2,
since the .NET Framework 4.7.1 is preinstalled with the operating system.
You can determine which versions of the .NET Framework are installed on a system.
See How to: Determine Which .NET Framework Versions Are Installed for more information.
In this table, 4.5.x refers to the .NET Framework 4.5 and its point releases, 4.5.1, and 4.5.2, 4.6.x
refers to the .NET Framework 4.6 and its point releases, 4.6.1 and 4.6.2,
4.7.x refers to the .NET Framework 4.7 and its point releases, 4.7.1 and 4.7.2, and 4.8 refers to .NET Framework 4.8.
Determine which .NET Framework versions are installed
Users can install and run multiple versions of the .NET Framework on their computers.
When you develop or deploy your app, you might need to know which .NET Framework versions are installed on the user’s computer.
The .NET Framework consists of two main components, which are versioned separately:
•A set of assemblies, which are collections of types and resources that provide the functionality for your apps.
The .NET Framework and assemblies share the same version number.
•The common language runtime (CLR), which manages and executes your app's code.
The CLR is identified by its own version number (see Versions and Dependencies).
Note
Each new version of the .NET Framework retains features from the previous versions and adds new features.
You can load multiple versions of the .NET Framework on a single computer at the same time,
which means that you can install the .NET Framework without having to uninstall previous versions.
In general, you shouldn't uninstall previous versions of the .NET Framework,
because an application you use may depend on a specific version and may break if that version is removed.
There is a difference between the .NET Framework version and the CLR version:
•The .NET Framework version is based on the set of assemblies that form the .NET Framework class library.
For example, .NET Framework versions include 4.5, 4.6.1, and 4.7.2.
•The CLR version is based on the runtime on which .NET Framework applications execute.
A single CLR version typically supports multiple .NET Framework versions.
For example, CLR version 4.0.30319.xxxxx supports .NET Framework versions 4 through 4.5.2 and CLR version 4.0.30319.42000
supports .NET Framework versions starting with .NET Framework 4.6.
For more information about versions, see .NET Framework versions and dependencies.
To get a list of the .NET Framework versions installed on a computer, you access the registry.
You can either use the Registry Editor to view the registry or use code to query it:
•Find newer .NET Framework versions (4.5 and later): ◦Use the Registry Editor to find .NET Framework versions
◦Use code to query the registry for .NET Framework versions
◦Use PowerShell to query the registry for .NET Framework versions
•Find older .NET Framework versions (1–4): ◦Use the Registry Editor to find .NET Framework versions
◦Use code to query the registry for .NET Framework versions
To get a list of the CLR versions installed on a computer, use a tool or code:
•Use the Clrver tool
•Use code to query the Environment class
For information about detecting the installed updates for each version of the .NET Framework,
Determine which .NET Framework updates are installed.
Find newer .NET Framework versions (4.5 and later)
Find .NET Framework versions 4.5 and later in the registry
1.From the Start menu, choose Run, enter regedit, and then select OK.
You must have administrative credentials to run regedit.
2.In the Registry Editor, open the following subkey: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\NET Framework Setup\NDP\v4\Full.
If the Full subkey isn't present, then you don't have the .NET Framework 4.5 or later installed.
Note : The NET Framework Setup folder in the registry does not begin with a period.
3.Check for a DWORD entry named Release.
If it exists, then you have .NET Framework 4.5 or later versions installed.
Its value is a release key that corresponds to a particular version of the .NET Framework.
for example, the value of the Release entry is 378389, which is the release key for .NET Framework 4.5.
Well when i read your MSG then i only see that you get a error abouth the .Net Frameworks ... But wat error CODE do it give ???