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Hi all,

Please go through the below code

PrincipalContext ctx = new PrincipalContext(ContextType.Domain, "","CN=Partition1,DC=Somename,DC=com", "AD/Administrator", "password");

While I run this code, I get a error message "The server could not be contacted"

inner exception "The LDAP server is unavailable".

Please let me know what to do.

Exception detail below

System.DirectoryServices.AccountManagement.PrincipalServerDownException was unhandled by user code
  Message=The server could not be contacted.
       at System.DirectoryServices.AccountManagement.PrincipalContext.ReadServerConfig(String serverName, ServerProperties& properties)
       at System.DirectoryServices.AccountManagement.PrincipalContext.DoServerVerifyAndPropRetrieval()
       at System.DirectoryServices.AccountManagement.PrincipalContext..ctor(ContextType contextType, String name, String container, ContextOptions options, String userName, String password)
       at System.DirectoryServices.AccountManagement.PrincipalContext..ctor(ContextType contextType)
       at TestingActiveDirectory._Default.Page_Load(Object sender, EventArgs e) in d:\TestingActiveDirectory\TestingActiveDirectory\Default.aspx.cs:line 88
       at System.Web.Util.CalliEventHandlerDelegateProxy.Callback(Object sender, EventArgs e)
       at System.Web.UI.Control.OnLoad(EventArgs e)
       at System.Web.UI.Control.LoadRecursive()
       at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)
  InnerException: System.DirectoryServices.Protocols.LdapException
       Message=The LDAP server is unavailable.
            at System.DirectoryServices.Protocols.LdapConnection.Connect()
            at System.DirectoryServices.Protocols.LdapConnection.SendRequestHelper(DirectoryRequest request, Int32& messageID)
            at System.DirectoryServices.Protocols.LdapConnection.SendRequest(DirectoryRequest request, TimeSpan requestTimeout)
            at System.DirectoryServices.Protocols.LdapConnection.SendRequest(DirectoryRequest request)
            at System.DirectoryServices.AccountManagement.PrincipalContext.ReadServerConfig(String serverName, ServerProperties& properties)

[edit]Code block added[/edit]
Posted 12-Jun-13 0:13am
Edited 12-Jun-13 1:03am
Bernhard Hiller 12-Jun-13 6:39am
Is that code run from a Windows application or by the web server?
Can you ping the LDAP server? What about the firewalls? Does the code work when run under a different user account?
Vignan Galla 12-Jun-13 7:51am
Thanks for your reply...
This code is run locally from a web application.
The computer and the server are on the same domain.
Yes, I am able to ping the LDAP server,please go through below.

Pinging [] with 32 bytes of data:
Reply from bytes=32 time<1ms TTL=128
Reply from bytes=32 time<1ms TTL=128
Reply from bytes=32 time<1ms TTL=128
Reply from bytes=32 time<1ms TTL=128

Ping statistics for
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 0ms, Maximum = 0ms, Average = 0ms

Regarding firewalls: for Domain,Private and Public windows firewall is off.
Do I need to disable/enable anything more regarding firewalls? Please help.

No the code does not run under any user account.
RyanDev 23-Sep-14 15:40pm
The error seems pretty clear. It can't connect to the LDAP server.

1 solution

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Solution 1

Please help me on this. I also stuck here and doesnt find any solution
RyanDev 23-Sep-14 15:39pm
This is not a solution. Please remove it.

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