exchange 2010 için ldap serveri değiştirme

Merhaba.exchange 2010 sunucusunda ldap serveri nasıl değiştirebilrim.Hala ortamda var olmayan bir dc yi ldap server olarak göreüyor.Bu yüzdende hiç bir kullanıcıyı sistemde göremiyorum.Yeni domain controllerime bütün ayarları aktardıma ama exchange sunucu üzerinden modify domain controller dediğimde hiç bir sunucu seçilmiyor.Hata aşağıdaki gibidir.

Microsoft.Exchange.Data.Directory.SuitabilityDirectoryException: An Active Directory error 0x51 occurred when trying to check the suitability of server 'abc.sirket.com.tr'. Error: 'Active directory response: The LDAP server is unavailable.' ---> System.DirectoryServices.Protocols.LdapException: The LDAP server is unavailable. at System.DirectoryServices.Protocols.LdapConnection.Connect() at System.DirectoryServices.Protocols.LdapConnection.BindHelper(NetworkCredential newCredential, Boolean needSetCredential) at Microsoft.Exchange.Data.Directory.SuitabilityVerifier.CreateConnectionAndBind(String fqdn, Int32 portNumber, NetworkCredential credential) --- End of inner exception stack trace --- at Microsoft.Exchange.Data.Directory.SuitabilityVerifier.CreateConnectionAndBind(String fqdn, Int32 portNumber, NetworkCredential credential) at Microsoft.Exchange.Data.Directory.SuitabilityVerifier.IsServerSuitable(String fqdn, Boolean isGlobalCatalog, NetworkCredential credential, String& writableNC, LocalizedString& errorMessage) at Microsoft.Exchange.Data.Directory.ConnectionPoolManager.GetConnection(ConnectionType connectionType, ADObjectId domain, String serverName, Int32 port, NetworkCredential credential) at Microsoft.Exchange.Data.Directory.ConnectionPoolManager.GetConnection(ConnectionType connectionType, NetworkCredential networkCredential, String serverName, Int32 port) at Microsoft.Exchange.Data.Directory.ADServerSettings.GetServerInfoFromFqdn(String fqdn, ConnectionType connectionType) at Microsoft.Exchange.Data.Directory.RunspaceServerSettings.SetUserPreferredGlobalCatalog(Fqdn fqdn) at Microsoft.Exchange.Management.ADServerSettings.SetAdServerSettings.InternalValidate() at Microsoft.Exchange.Configuration.Tasks.Task.ProcessRecord()
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