活动目录使用LDAP认证。服务器无法运行的错误

我域名ajcserver。当我的呼唤"的LDAP :/ / ajcserver的/ DC = ajcserver"。然后
服务器不可操作显示。我的域名是无效或不？
但是当我打电话的"LDAP :/ / 196.1.1.253/DC = ajcserver的"，它是工作的罚款。我的DNS名称是AJCSRVR
错误如下。普莱舍普莱舍帮助我

[COMException (0x8007203a): The server is not operational]

   System.DirectoryServices.DirectoryEntry.Bind(Boolean throwIfFail)

   System.DirectoryServices.DirectoryEntry.Bind()

   System.DirectoryServices.DirectoryEntry.get_NativeObject()

   ActiveDirectoryCheck.FormsAuthAD.LdapAuthentication.IsAuthenticated(String domain, String username, String pwd) in C:\Inetpub\wwwroot\ActiveDirectoryCheck\LdapAuthentication.vb:41

   ActiveDirectoryCheck.Logon.btnLogon_Click(Object sender, EventArgs e) in C:\Inetpub\wwwroot\ActiveDirectoryCheck\Logon.aspx.vb:51

   System.Web.UI.WebControls.Button.OnClick(EventArgs e)

   System.Web.UI.WebControls.Button.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument)

   System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument)

   System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData)

   System.Web.UI.Page.ProcessRequestMain() +1292