What is .Net framework?

 The .NET Framework is a software development framework developed by Microsoft that provides a comprehensive and consistent programming model for building and running applications on Windows-based operating systems. The .NET Framework supports multiple programming languages, including C#, Visual Basic.NET (VB.NET), F#, and more.

If an application is designed in .Net that the system should have the appropriate .Net framework version installed in that server/PC. Or else application will not run in your server.We can download and install.Net framework from online by searching “Download .Net framework” online

.Net versions: 2.0, 3.0, 4.0, 4.5, 4.5.1, 4.5.2, 4.6 4.6.1, 4.6.2, 4.7.1,4.7.2,4.8(Running Version)

How to Download & Install .Net Framework in Windows Server?

Download link for .Net Framework: https://dotnet.microsoft.com/en-us/download/dotnet-framework

We can install the different versions of .net frameworks in the following Path: C:/WINDOWS/Microsoft.net/Framework

How to check .Net Version in Windows Server?

1. Using Command Prompt or PowerShell: Open Command Prompt or PowerShell with administrative privileges (right-click and choose "Run as administrator") and run the following command: reg query "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\NET Framework Setup\NDP" /s

2.Using Registry Editor :Press the Windows key + R to open the Run dialog, then type regedit and press Enter. This will open the Registry Editor. Navigate to the following registry key: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\NET Framework Setup\NDP

How to Register .Net Framework with IIS?

We must run the below commands in command prompt to register .Net framework with IIS. We have to run these commands in the .Net framework path from CMD

aspnet_regiis -i	Installs ASP.NET 4 and updates existing applications
aspnet_regiis -u	Uninstalls ASP.NET Versions
aspnet_regiis -disable	Disables the ASP.NET ISAPI extension
aspnet_regiis -enable	Enables the ASP.NET ISAPI extension
aspnet_regiis -lv	List the status and installation path of all versions of ASP.NET
aspnet_regiis -?	Displays the command syntaxes for the ASP.NET IIS Registration tool

Example: 

C:\Windows\Microsoft.NET\Framework\v4.0.30319>aspnet_regiis.exe -i

Microsoft (R) ASP.NET RegIIS version 4.0.30319.0

Administration utility to install and uninstall ASP.NET on the local machine.

Copyright (C) Microsoft Corporation.  All rights reserved.

Start installing ASP.NET (4.0.30319.0).

This option is not supported on this version of the operating system.  Administrators should instead install/uninstall ASP.NET 4.5 with IIS8 using the "Turn Windows Features On/Off" dialog,  the Server Manager management tool, or the dism.exe command line tool.  For more details please see http://go.microsoft.com/fwlink/?LinkID=216771.

Finished installing ASP.NET (4.0.30319.0).