How to login to Active Directory?

Question

I have a username and password for active directory and I want login to active directory using C#. How I can do this in Windows Forms?

So do you want to login into Active Directory or into Windows Server which is into a domain? — abatishchev, Jul 26 '12 at 08:26
You keep repeating that - elaborate! What is it you want to do? What do you want to _accomplish_? — J. Steen, Jul 26 '12 at 08:40

score 6 · Answer 1 · edited May 23 '17 at 12:33

This Question is from a couple of years ago, I hope this answer can help people in the future. This is working for me:

Add these references:

using System.DirectoryServices;
using System.DirectoryServices.AccountManagement;

After that, you can use this code in your app:

   PrincipalContext pc = new PrincipalContext(ContextType.Domain, "YOUR DOMAIN");
   bool Valid = pc.ValidateCredentials("User", "password");

The variable called: Valid, will show you a True value if the logIn is Ok.

For more information you can visit this page. The page is from here, stackOverFlow, and it will show you a lot of information about: "login with MS Active Directory"

score 5 · Answer 2 · edited Jun 20 '20 at 09:12

5

Solution

Connecting to an Active Directory is very easy.

You must use the DirectoryEntry object (in the namespace System.DirectoryServices).

The constructor for this object takes three strings in parameters:

the path to the Active Directory. This path has the format: LDAP://your-name-AD
the username for the connection
the corresponding password

Example

using System.DirectoryServices;

try
{
   DirectoryEntry Ldap = new DirectoryEntry("LDAP://your-name-AD", "Login", "Password");
}
catch(Exception Ex)
{
   Console.WriteLine(Ex.Message);
}

edited Jun 20 '20 at 09:12

Community

1
1

answered Jul 26 '12 at 08:24

GG.

21,083
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what is `DirectoryEntry`? I want to user `using System.Security.Principal;` thanks – Arian Jul 26 '12 at 08:26
What is difference between your solution and `NetworkCredential cred = new NetworkCredential("User", "Pass", "Domain");`? can you explain more please – Arian Jul 26 '12 at 08:37
[`DirectoryEntry`](http://msdn.microsoft.com/en-us//library/system.directoryservices.directoryentry(v=vs.80).aspx) handles all actions performed on an AD ; not [`NetworkCredential`](http://msdn.microsoft.com/en-us//library/system.net.networkcredential(v=vs.80).aspx). – GG. Jul 26 '12 at 08:56

Alex · Accepted Answer · 2012-07-26T09:02:48.003

There you go. This method validates username/password against Active Directory, and has been a part of my toolbox of functions for quite some time.

//NOTE: This can be made static with no modifications
public bool ActiveDirectoryAuthenticate(string username, string password)
{
    bool result = false;
    using (DirectoryEntry _entry = new DirectoryEntry())
    {
        _entry.Username = username;
        _entry.Password = password;
        DirectorySearcher _searcher = new DirectorySearcher(_entry);
        _searcher.Filter = "(objectclass=user)";
        try
        {
            SearchResult _sr = _searcher.FindOne();
            string _name = _sr.Properties["displayname"][0].ToString();
            result = true;
        }
        catch
        { /* Error handling omitted to keep code short: remember to handle exceptions !*/ }
    }

    return result; //true = user authenticated!
}

The software executing this must be run on a computer inside the domain, obviously (or you would have no Active Directory to authenticate your credentials against).

What is difference between your solution and NetworkCredential cred = new NetworkCredential("User", "Pass", "Domain");? can you explain more please — Arian, Jul 26 '12 at 08:51
NetworkCredential is just an object with some data inside, it doesn't validate anything. — Alex, Jul 26 '12 at 09:01

score 1 · Answer 4 · answered Jan 12 '16 at 06:05

1

a shorter answer is to add the reference System.DirectoryServices.AccountManagement

Then use UserPrincipal.Current.Context.ValidateCredentials("username", "password");

But i guess you will need to be joined to the domain you want to validate for.

answered Jan 12 '16 at 06:05

Mohammed AlJasim

11
1

Thanks for the answer! But I encountered an DirectoryOperationException with the code above, and I solved it by adding the third parameter "ContextOptions.Negotiate". – HCH Mar 23 '22 at 08:54

How to login to Active Directory?

4 Answers4

Solution

Example