We Keep Coding

Connect to LDAP server and hit error in ASP.NET C# webform

I am using Windows authentication in a Webforms application, and I want to get the user's email address, but I think I hit the error when connecting to the server. Anything wrong with my code?
I had tried the strAccountId with/without domain name, (sAMAccountName=john).
The server is not operational.
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.
Exception Details: System.Runtime.InteropServices.COMException: The server is not operational
Code:
string path = "LDAP://XYZ.LOCAL/CN=XYZ.LOCAL,OU=XXX,DC=XYZ,DC=LOCAL";
// The value of User.Identity.Name is XYZ\john
string strAccountId = "XYZ\\john";
string strPassword = "xxxxx";
bool bSucceeded;
string strError;
DirectoryEntry adsEntry = new DirectoryEntry(path, strAccountId, strPassword);
DirectorySearcher adsSearcher = new DirectorySearcher(adsEntry);
adsSearcher.Filter = "(sAMAccountName=" + strAccountId + ")";
try
{
SearchResult adsSearchResult = adsSearcher.FindOne();
bSucceeded = true;
strError = "User has been authenticated by Active Directory.";
EmailMsg.Text = strError;
adsEntry.Close();
}
catch (Exception ex)
{
bSucceeded = false;
strError = ex.Message;
EmailMsg.Text = strError;
adsEntry.Close();
}

In path you cannot put OUs, you need to do that after with adsEntry.Path.
string path = "LDAP://XYZ.LOCAL";
string strAccountId = "XYZ.LOCAL\\john";
string strPassword = "xxxxx";
DirectoryEntry adsEntry = new DirectoryEntry(path, strAccountId, strPassword);
adsEntry.Path = "LDAP://CN=XYZ.LOCAL,OU=XXX,DC=XYZ,DC=LOCAL";

Your path has three parts:
LDAP:// is the protocol
XYZ.LOCAL is the server to connect to. This is optional and can be excluded if the computer you run this from is joined to the same domain you're trying to connect to, or to a trusted domain.
CN=XYZ.LOCAL,OU=XXX,DC=XYZ,DC=LOCAL is the object on the domain to bind to. This is also optional. If excluded, it will bind to the root of the domain that the server in part 2 is part of. You must include either part 2 or 3, or both.
Since you have included the optional server name, it will try to connect to XYZ.LOCAL on the default LDAP port 389. "The server is not operational" means that it could not open a connection to XYZ.LOCAL on port 389. This is a network error and you need to figure out why the domain is not accessible from the computer you are running this from.
You can test the connection in PowerShell using:
Test-NetConnection XYZ.LOCAL -Port 389

connect active directory using c#

i m trying to connect to Active Directory code that i have used
string domain = "domain.com.pk";
string container = "DC=mycompnay,DC=com,DC=pk";
string Admin = "salman.zafar";
string Password = "password";
using (PrincipalContext pc = new PrincipalContext(ContextType.Domain, domain, container, Admin, Password))
{
string userPrincipalName = "dotnettest" + "#" + domain;
// validate the credentials
bool isValid = pc.ValidateCredentials(userPrincipalName, "Ascertia 12");
if (isValid) {
UserPrincipal up = UserPrincipal.FindByIdentity(pc, IdentityType.UserPrincipalName, userPrincipalName);
}
code works fine when the code running on machine which is in domain but if i try to connect to the AD machine that is remote then i get error
i tried to use
string domain = "192.168.0.150:389/domain.com.pk";
then it didn't work and validate credentials method always return false can some one help me how can i connect to remote active directory using IP with port with PrincipalContext or i have to use directory entry
any help will be appreciated

First note:
code works fine when the code running on machine which is in domain
In this case, you do not need to provide adminuser+pw in the PrincipalContext constructor if the machine is a domain member (which I assume here).
If you want to connect to any other AD server (domain controller) with no trust between the foreign domain and the current domain, use the IP address or server name as the "domain" name:
string domain = "192.168.0.150";
If your goal is to just check if credentials are valid, you can even omit the admin user + pw:
string domainController = "192.168.0.150";
using (PrincipalContext pc = new PrincipalContext(ContextType.Domain, domainController))
{
string userPrincipalName = "dotnettest" + "#" + domain;
// validate the credentials
bool isValid = pc.ValidateCredentials(userPrincipalName, "Ascertia 12");
}
In this case, however, you cannot have
UserPrincipal up = UserPrincipal.FindByIdentity(...
because the PrincipalContext itself is not logged on.
You can also see my answer in a similar question: https://stackoverflow.com/a/28690682/4547223
or this SO article Validate a username and password against Active Directory?

Searching through Active Directory in C# and authenticate with current User

What i want to do:
A user is logged into my application with his user credentials. A form has as input only a pNumber, the application should search through active directory to find the user with that number and fill out different input fields automatically (in this example only name and email).
What i already have (C# Code, .Net 4.0):
public static string[] getUser(string pNumber) {
string[] user = new string[4];
NetworkCredential credential = CredentialCache.DefaultNetworkCredentials;
string userName = System.Security.Principal.WindowsIdentity.GetCurrent().Name;
string DomainPath = "LDAP://DC=****,DC=com";
string strAccountId = userName;
string strPassword = "******";
DirectoryEntry adsEntry = new DirectoryEntry(DomainPath, strAccountId, strPassword);
DirectorySearcher adsSearcher = new DirectorySearcher(adsEntry);
adsSearcher.Filter = "(pNumber=" + pNumber + ")";
SearchResult adsSearchResult = adsSearcher.FindOne();
if (adsSearchResult != null) {
user[0] = adsSearchResult.Properties["sAMAccountName"][0].ToString();
user[1] = adsSearchResult.Properties["mail"][0].ToString();
}
return user;
}
If i put in values for strAccountId and strPassword i know have access to AD this works fine. But this is only a workaround. I would like to authenticate to AD with the current users credentials. I can get the current username, but i think it is not possible to get the password. So i looked into other posibilitys to authenticate with DirectoryEntry here. (What i didnt really get was the DirectoryEntry(Object) Constructor)
My Question:
Are there alternatives i can search through AD with C# with the current user credentials?

DirectorySearcher ds = new DirectorySearcher(de);
if the current user has access it will be good if not you get an exception.

LDAP C# error when trying to connect

I keep getting the following error when trying to connect to an LDAP server. The user name or password is incorrect.
It occurs on the .FindOne()
If I use AuthenticationTypes.Encryption i get an error: The server is not operational.
I've also tried to prepend the username with ownme\username
I'm extremely newbish with AD so the issue might be so simple.
Domain = domain;
_entry = new DirectoryEntry("LDAP://DC1/DC=ownme,DC=local", username, password, AuthenticationTypes.ServerBind);
_directorySearcher = new DirectorySearcher(_entry, "(objectClass=*)", new string[] {"namingContexts"}, SearchScope.Subtree);
var namingContext = _directorySearcher.FindOne();

The problem was credentials. You need to specify the domain prefix in the username or look at one of the comments in my question.
I had var username = "domain\username";
I should have written var username = #"domain\username";

The LDAP server is unavailable

I'm a total newbie to this
Trying to connect to an ldap server with PrincipalContext. I have tried all solutions on this site to no avail.
Things I've tried:
PrincipalContext insPrincipalContext =
new PrincipalContext(ContextType.Domain);
PrincipalContext insPrincipalContext =
new PrincipalContext(ContextType.Domain, "ldap://localhost:389/dc=maxcrc,dc=com");
PrincipalContext insPrincipalContext =
new PrincipalContext(ContextType.Domain, "maxcrc.com");
All give the same result:
LDAP server not available
Only ContextType.Machine works basically.
Not sure if my LDAP server is set up correctly:
Host: localhost
Port: 389
Base DN: dc=maxcrc,dc=com
URL: ldap://localhost:389/dc=maxcrc,dc=com
Testing with Softerra LDAP Browser
Any tutorials from start to finish will be much appreciated...

I have been facing the same issue and I found a solution.
I'm able to connect easily using following code:
ADUser_Id = "domainName\\username"; //make sure user name has domain name.
Password = "xxxx";
var context = new PrincipalContext(ContextType.Domain,"server_address", ADUser_Id,Password);
/* server_address = "192.168.15.36"; //don't include ldap in url */

I had similar issues. It turned out that I had to pass username and password in the object initialization. Please try using a statement like below:
PrincipalContext insPrincipalContext =
new PrincipalContext(ContextType.Domain,
"ldap://localhost:389/dc=maxcrc,dc=com",
userName,
password);
Also make sure that your username has domain in it.
For example,
userName = "mydomainname" + "\\" + "john_jacobs"

Use the following constructor overload for PrincipalContext:
public PrincipalContext(
ContextType contextType,
string name,
string container
)
And separate the server name from the LDAP string:
PrincipalContext insPrincipalContext =
new PrincipalContext(ContextType.Domain, "localhost:389", "dc=maxcrc,dc=com");
https://msdn.microsoft.com/en-us/library/bb348316%28v=vs.110%29.aspx

In my environment I had to create the principal context with just the domain controller host name, and then separately validate the user credentials.
string domainControllerName = "PDC";
string domainName = "MyDomain"; // leave out the .Local, this is just to use as the prefix for the username if the user left it off or didn't use the principal address notation
string username = "TestUser";
string password = "password";
using (var ldap = new PrincipalContext(ContextType.Domain, domainControllerName))
{
var usernameToValidate = username;
if (!usernameToValidate.Any(c => c == '#' || c == '\\'))
usernameToValidate = $"{domainName}\\{username}";
if (!ldap.ValidateCredentials(username, context.Password, ContextOptions.SimpleBind))
throw new UnauthorizedException();
}
This example allows for all three of these variations to the username to validate:
TestUser
MyDomain\TestUser
TestUser#MyDomain.Local

You may want to try your local machine address instead :
ldap://127.0.0.1:389/dc=maxcrc,dc=com
If that doesn't work, I'd fire up Wireshark, and have it capture traffic on port 389 as you're attempting to connect via Softerra.
In my time working with LDAP and .Net DirectoryServices, that error usually means the syntax or naming convention of the path is incorrect, or does not point to a valid directory end point.

That error might be due to trying to connect as "Anonymous" without specifying it explicitly.
By default all connections are Negotiable. So if you try something like that you could try the following:
LdapDirectoryIdentifier ldap = new LdapDirectoryIdentifier("My Hostname or IP Address",10389); //10389 might be your non default port
LdapConnection connection = new LdapConnection(ldap);
connection.AuthType = AuthType.Anonymous;