292
votes

A similar question was asked here, but it was specific to .NET 3.5. Specifically, I'm looking for the following:

  1. What is the correct way to determine which .NET Framework versions and service packs are installed?
  2. Is there a list of registry keys that can be used?
  3. Are there any dependencies between Framework versions?
13
Yes, it is. I already knew about the first one (it's the one I refer to in my question). I didn't know about the other one.Scott Dorman
I'm impressed how this question (including answers) and all the closely related questions entirely ignore the presence of the SKU values -- this even differentiates between 4.5 and 4.5.1.springy76
@springy76, The reason this doesn't address the presence of SKU values is because, for the purposes of determining which versions of the Framework are installed, they aren't relevant. The question you refer to is actually trying to determine if ".NET 4.0.2" is installed. The problem here is that there was no .NET 4.0.2, it was an update (KB2544514), not a Framework release or a service pack. You can look at this article on MSDN (msdn.microsoft.com/en-us/library/hh925567(v=vs.110).aspx) for more information on how to detect which updates are installed.Scott Dorman

13 Answers

368
votes

The registry is the official way to detect if a specific version of the Framework is installed.

enter image description here

Which registry keys are needed change depending on the Framework version you are looking for:

Framework Version  Registry Key
------------------------------------------------------------------------------------------
1.0                HKLM\Software\Microsoft\.NETFramework\Policy\v1.0\3705 
1.1                HKLM\Software\Microsoft\NET Framework Setup\NDP\v1.1.4322\Install 
2.0                HKLM\Software\Microsoft\NET Framework Setup\NDP\v2.0.50727\Install 
3.0                HKLM\Software\Microsoft\NET Framework Setup\NDP\v3.0\Setup\InstallSuccess 
3.5                HKLM\Software\Microsoft\NET Framework Setup\NDP\v3.5\Install 
4.0 Client Profile HKLM\Software\Microsoft\NET Framework Setup\NDP\v4\Client\Install
4.0 Full Profile   HKLM\Software\Microsoft\NET Framework Setup\NDP\v4\Full\Install

Generally you are looking for:

"Install"=dword:00000001

except for .NET 1.0, where the value is a string (REG_SZ) rather than a number (REG_DWORD).

Determining the service pack level follows a similar pattern:

Framework Version  Registry Key
------------------------------------------------------------------------------------------
1.0                HKLM\Software\Microsoft\Active Setup\Installed Components\{78705f0d-e8db-4b2d-8193-982bdda15ecd}\Version 
1.0[1]             HKLM\Software\Microsoft\Active Setup\Installed Components\{FDC11A6F-17D1-48f9-9EA3-9051954BAA24}\Version 
1.1                HKLM\Software\Microsoft\NET Framework Setup\NDP\v1.1.4322\SP 
2.0                HKLM\Software\Microsoft\NET Framework Setup\NDP\v2.0.50727\SP 
3.0                HKLM\Software\Microsoft\NET Framework Setup\NDP\v3.0\SP 
3.5                HKLM\Software\Microsoft\NET Framework Setup\NDP\v3.5\SP 
4.0 Client Profile HKLM\Software\Microsoft\NET Framework Setup\NDP\v4\Client\Servicing
4.0 Full Profile   HKLM\Software\Microsoft\NET Framework Setup\NDP\v4\Full\Servicing

[1] Windows Media Center or Windows XP Tablet Edition

As you can see, determining the SP level for .NET 1.0 changes if you are running on Windows Media Center or Windows XP Tablet Edition. Again, .NET 1.0 uses a string value while all of the others use a DWORD.

For .NET 1.0 the string value at either of these keys has a format of #,#,####,#. The last # is the Service Pack level.

While I didn't explicitly ask for this, if you want to know the exact version number of the Framework you would use these registry keys:

Framework Version  Registry Key
------------------------------------------------------------------------------------------
1.0                HKLM\Software\Microsoft\Active Setup\Installed Components\{78705f0d-e8db-4b2d-8193-982bdda15ecd}\Version 
1.0[1]             HKLM\Software\Microsoft\Active Setup\Installed Components\{FDC11A6F-17D1-48f9-9EA3-9051954BAA24}\Version 
1.1                HKLM\Software\Microsoft\NET Framework Setup\NDP\v1.1.4322 
2.0[2]             HKLM\Software\Microsoft\NET Framework Setup\NDP\v2.0.50727\Version 
2.0[3]             HKLM\Software\Microsoft\NET Framework Setup\NDP\v2.0.50727\Increment
3.0                HKLM\Software\Microsoft\NET Framework Setup\NDP\v3.0\Version 
3.5                HKLM\Software\Microsoft\NET Framework Setup\NDP\v3.5\Version 
4.0 Client Profile HKLM\Software\Microsoft\NET Framework Setup\NDP\v4\Version 
4.0 Full Profile   HKLM\Software\Microsoft\NET Framework Setup\NDP\v4\Version 

[1] Windows Media Center or Windows XP Tablet Edition
[2] .NET 2.0 SP1
[3] .NET 2.0 Original Release (RTM)

Again, .NET 1.0 uses a string value while all of the others use a DWORD.

Additional Notes

  • for .NET 1.0 the string value at either of these keys has a format of #,#,####,#. The #,#,#### portion of the string is the Framework version.

  • for .NET 1.1, we use the name of the registry key itself, which represents the version number.

  • Finally, if you look at dependencies, .NET 3.0 adds additional functionality to .NET 2.0 so both .NET 2.0 and .NET 3.0 must both evaulate as being installed to correctly say that .NET 3.0 is installed. Likewise, .NET 3.5 adds additional functionality to .NET 2.0 and .NET 3.0, so .NET 2.0, .NET 3.0, and .NET 3. should all evaluate to being installed to correctly say that .NET 3.5 is installed.

  • .NET 4.0 installs a new version of the CLR (CLR version 4.0) which can run side-by-side with CLR 2.0.

Update for .NET 4.5

There won't be a v4.5 key in the registry if .NET 4.5 is installed. Instead you have to check if the HKLM\Software\Microsoft\NET Framework Setup\NDP\v4\Full key contains a value called Release. If this value is present, .NET 4.5 is installed, otherwise it is not. More details can be found here and here.

17
votes

There is an official Microsoft answer to this question at the following knowledge base article:

Article ID: 318785 - Last Review: November 7, 2008 - Revision: 20.1 How to determine which versions of the .NET Framework are installed and whether service packs have been applied

Unfortunately, it doesn't appear to work, because the mscorlib.dll version in the 2.0 directory has a 2.0 version, and there is no mscorlib.dll version in either the 3.0 or 3.5 directories even though 3.5 SP1 is installed ... why would the official Microsoft answer be so misinformed?

16
votes

The Framework 4 beta installs to a differing registry key.

using System;
using System.Collections.ObjectModel;
using Microsoft.Win32;

class Program
{
    static void Main(string[] args)
    {
        foreach(Version ver in InstalledDotNetVersions())
            Console.WriteLine(ver);

        Console.ReadKey();
    }


    public static Collection<Version> InstalledDotNetVersions()
    {
        Collection<Version> versions = new Collection<Version>();
        RegistryKey NDPKey = Registry.LocalMachine.OpenSubKey(@"SOFTWARE\Microsoft\NET Framework Setup\NDP");
        if (NDPKey != null)
        {
            string[] subkeys = NDPKey.GetSubKeyNames();
            foreach (string subkey in subkeys)
            {
                GetDotNetVersion(NDPKey.OpenSubKey(subkey), subkey, versions);
                GetDotNetVersion(NDPKey.OpenSubKey(subkey).OpenSubKey("Client"), subkey, versions);
                GetDotNetVersion(NDPKey.OpenSubKey(subkey).OpenSubKey("Full"), subkey, versions);
            }
        }
        return versions;
    }

    private static void GetDotNetVersion(RegistryKey parentKey, string subVersionName, Collection<Version> versions)
    {
        if (parentKey != null)
        {
            string installed = Convert.ToString(parentKey.GetValue("Install"));
            if (installed == "1")
            {
                string version = Convert.ToString(parentKey.GetValue("Version"));
                if (string.IsNullOrEmpty(version))
                {
                    if (subVersionName.StartsWith("v"))
                        version = subVersionName.Substring(1);
                    else
                        version = subVersionName;
                }

                Version ver = new Version(version);

                if (!versions.Contains(ver))
                    versions.Add(ver);
            }
        }
    }
}
8
votes

I wanted to detect for the presence of .NET version 4.5.2 installed on my system, and I found no better solution than ASoft .NET Version Detector.

Snapshot of this tool showing different .NET versions:

Snapshot of this tool showing different .NET versions

7
votes

Enumerate the subkeys of HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\NET Framework Setup\NDP. Each subkey is a .NET version. It should have Install=1 value if it's present on the machine, an SP value that shows the service pack and an MSI=1 value if it was installed using an MSI. (.NET 2.0 on Windows Vista doesn't have the last one for example, as it is part of the OS.)

5
votes

For a 64-bit OS, the path would be:

HKEY_LOCAL_MACHINE\SOFTWARE\wow6432Node\Microsoft\NET Framework Setup\NDP\
5
votes

Update for .NET 4.5.1

Now that .NET 4.5.1 is available the actual value of the key named Release in the registry needs to be checked, not just its existence. A value of 378758 means that .NET Framework 4.5.1 is installed. However, as described here this value is 378675 on Windows 8.1.

5
votes

There is a GUI tool available, ASoft .NET Version Detector, which has always proven highly reliable. It can create XML files by specifying the file name of the XML output on the command line.

You could use this for automation. It is a tiny program, written in a non-.NET dependent language and does not require installation.

4
votes

I was needing to find out just which version of .NET framework I had on my computer, and all I did was go to the control panel and select the "Uninstall a Program" option. After that, I sorted the programs by name, and found Microsoft .NET Framework 4 Client Profile.

3
votes

Here is a PowerShell script to obtain installed .NET framework versions

function Get-KeyPropertyValue($key, $property)
{
    if($key.Property -contains $property)
    {
        Get-ItemProperty $key.PSPath -name $property | select -expand $property
    }
}

function Get-VersionName($key)
{
   $name = Get-KeyPropertyValue $key Version
   $sp = Get-KeyPropertyValue $key SP
   $install = Get-KeyPropertyValue $key Install
   if($sp)
   {
        "$($_.PSChildName) $name SP $sp"
   }
   else{
    "$($_.PSChildName) $name"
   }
}

function Get-FrameworkVersion{
   dir "hklm:\SOFTWARE\Microsoft\NET Framework Setup\NDP\" |? {$_.PSChildName -like "v*"} |%{
    if( $_.Property -contains "Version")
    {
        Get-VersionName $_
    }
    else{
        $parent = $_
        Get-ChildItem $_.PSPath |%{
            $versionName = Get-VersionName $_
            "$($parent.PSChildName) $versionName"
            }
        }
    }
}


$v4Directory = "hklm:\SOFTWARE\Microsoft\NET Framework Setup\NDP\v4\Full"
if(Test-Path $v4Directory)
{
    $v4 = Get-Item $v4Directory
    $version = Get-KeyPropertyValue $v4 Release
    switch($version){
        378389 {".NET Framework 4.5"; break;}
        378675 {".NET Framework 4.5.1 installed with Windows 8.1 or Windows Server 2012 R2"; break;}
        378758 {".NET Framework 4.5.1 installed on Windows 8, Windows 7 SP1, or Windows Vista SP2"; break;}
        379893 {".NET Framework 4.5.2"; break;}
        { 393295, 393297 -contains $_} {".NET Framework 4.6"; break;}
        { 394254, 394271 -contains $_} {".NET Framework 4.6.1"; break;}
        { 394802, 394806 -contains $_} {".NET Framework 4.6.2"; break; }
    }
}

It was written based on How to: Determine Which .NET Framework Versions Are Installed. Please use THE Get-FrameworkVersion() function to get information about installed .NET framework versions.

2
votes

Using the Signum.Utilities library from SignumFramework (which you can use stand-alone), you can get it nicely and without dealing with the registry by yourself:

AboutTools.FrameworkVersions().ToConsole();
//Writes in my machine:
//v2.0.50727 SP2
//v3.0 SP2
//v3.5 SP1
1
votes

See How to: Determine Which .NET Framework Versions Are Installed (MSDN).

MSDN proposes one function example that seems to do the job for version 1-4. According to the article, the method output is:

v2.0.50727  2.0.50727.4016  SP2
v3.0  3.0.30729.4037  SP2
v3.5  3.5.30729.01  SP1
v4
  Client  4.0.30319
  Full  4.0.30319

Note that for "versions 4.5 and later" there is another function.

1
votes

In Windows 7 (it should work for Windows 8 also, but I haven't tested it):

Go to a command prompt

Steps to go to a command prompt:

  1. Click Start Menu
  2. In Search Box, type "cmd" (without quotes)
  3. Open cmd.exe

In cmd, type this command

wmic /namespace:\\root\cimv2 path win32_product where "name like '%%.NET%%'" get version

This gives the latest version of NET Framework installed.

One can also try Raymond.cc Utilties for the same.