[asp.net] How to check ASP.NET Version loaded on a system?

How can I check the version of ASP.NET that is installed on my system?

Here is some code that will return the installed .NET details:

<%@ Page Language="VB" Debug="true" %>
<%@ Import namespace="System" %>
<%@ Import namespace="System.IO" %>
<% 
Dim cmnNETver, cmnNETdiv, aspNETver, aspNETdiv As Object
Dim winOSver, cmnNETfix, aspNETfil(2), aspNETtxt(2), aspNETpth(2), aspNETfix(2) As String

winOSver = Environment.OSVersion.ToString
cmnNETver = Environment.Version.ToString
cmnNETdiv = cmnNETver.Split(".")
cmnNETfix = "v" & cmnNETdiv(0) & "." & cmnNETdiv(1) & "." & cmnNETdiv(2)

For filndx As Integer = 0 To 2
  aspNETfil(0) = "ngen.exe"
  aspNETfil(1) = "clr.dll"
  aspNETfil(2) = "KernelBase.dll"

  If filndx = 2   
    aspNETpth(filndx) = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.System), aspNETfil(filndx))
  Else
    aspNETpth(filndx) = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.Windows), "Microsoft.NET\Framework64", cmnNETfix, aspNETfil(filndx))
  End If

  If File.Exists(aspNETpth(filndx)) Then
    aspNETver = Diagnostics.FileVersionInfo.GetVersionInfo(aspNETpth(filndx))
    aspNETtxt(filndx) = aspNETver.FileVersion.ToString
    aspNETdiv = aspNETtxt(filndx).Split(" ")
    aspNETfix(filndx) = aspNETdiv(0)
  Else
    aspNETfix(filndx) = "Path not found... No version found..."
  End If
Next

Response.Write("Common MS.NET Version (raw): " & cmnNETver & "<br>")
Response.Write("Common MS.NET path: " & cmnNETfix & "<br>")
Response.Write("Microsoft.NET full path: " & aspNETpth(0) & "<br>")
Response.Write("Microsoft.NET Version (raw): " & aspNETtxt(0) & "<br>")
Response.Write("<b>Microsoft.NET Version: " & aspNETfix(0) & "</b><br>")
Response.Write("ASP.NET full path: " & aspNETpth(1) & "<br>")
Response.Write("ASP.NET Version (raw): " & aspNETtxt(1) & "<br>")
Response.Write("<b>ASP.NET Version: " & aspNETfix(1) & "</b><br>")
Response.Write("OS Version (system): " & winOSver & "<br>")
Response.Write("OS Version full path: " & aspNETpth(2) & "<br>")
Response.Write("OS Version (raw): " & aspNETtxt(2) & "<br>")
Response.Write("<b>OS Version: " & aspNETfix(2) & "</b><br>")
%>

Here is the new output, cleaner code, more output:

Common MS.NET Version (raw): 4.0.30319.42000
Common MS.NET path: v4.0.30319
Microsoft.NET full path: C:\Windows\Microsoft.NET\Framework64\v4.0.30319\ngen.exe
Microsoft.NET Version (raw): 4.6.1586.0 built by: NETFXREL2
Microsoft.NET Version: 4.6.1586.0
ASP.NET full path: C:\Windows\Microsoft.NET\Framework64\v4.0.30319\clr.dll
ASP.NET Version (raw): 4.7.2110.0 built by: NET47REL1LAST
ASP.NET Version: 4.7.2110.0
OS Version (system): Microsoft Windows NT 10.0.14393.0
OS Version full path: C:\Windows\system32\KernelBase.dll
OS Version (raw): 10.0.14393.1715 (rs1_release_inmarket.170906-1810)
OS Version: 10.0.14393.1715

I needed this information too and got information with this method,

Launch PowerShell

run the 'import-module servermanager' command ( without quotes )

after that for asp.net 3.5 check run the 'get-windowsfeature web-asp-net' command ( without quotes )

for asp.net 4.5 check run the 'get-windowsfeature Net-Framework-45-Core' command ( without quotes )

Both of the commands will inform you below Install State header.

Detecting version via GUI in server environment and details can be found in this link.

Look in c:\windows\Microsoft.NET\Framework and you will see various folders starting with "v" indicating the versions of .NET installed.

open a new command prompt and run the following command: dotnet --info

I had same problem to find a way to check whether ASP.NET 4.5 is on the Server. Because v4.5 is in place replace to v4.0, if you look at c:\windows\Microsoft.NET\Framework, you will not see v4.5 folder. Actually there is a simple way to see the version installed in the machine. Under Windows Server 2008 or Windows 7, just go to control panel -> Programs and Features, you will find "Microsoft .NET Framework 4.5" if it is installed.

Alternatively, you can create a button on your webpage and in the Page_Load type;

Trace.IsEnabled = True

And in the button click event type;

Response.Write(Trace)

This will bring up all the trace information and you will find your ASP.NET version in the "Response Headers Collection" under "X-ASPNet-Version".

You can see which version gets executed when you load the page with Google Chrome + developer tools (preinstalled) or Firefox + Firebug (add-on).

I use Google Chrome:

1. Open Chrome and use Ctrl+Shift+I to open the developer tools.
2. Go to the "Network" Tab
3. Click on the small button at the bottom "Preserve log upon Navigation"
4. Load any of your pages
5. Click on the response header

It looks like this:

You can use

<%
Response.Write("Version: " + System.Environment.Version.ToString());
%>

That will get the currently running version. You can check the registry for all installed versions at:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\NET Framework Setup\NDP