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Home > Success Center > Network Configuration Manager (NCM) > NCM - Knowledgebase Articles > NCM displays the error Unable to connect to polling engine XXXXXXX on the relevant server

NCM displays the error Unable to connect to polling engine XXXXXXX on the relevant server

Updated February 28, 2018


This article describes what to check if you encounter the following error when you try to access NCM jobs: 


Unable to connect to polling engine XXXXXXX on the relevant server. Verify that NCM 7.7 or later is installed on the server


The error above can be generic in nature.The resolution below is specific to a particular issue that can be identified by a particular error.


If you see the error above on the Orion Web Console, refer to the server name in the error and look in the NCM Business Layer Plugin log in the following directory:




If you find the following error, follow the instructions in the Resolution section:


FATAL SolarWinds.NCM.BusinessLayerPlugin.NcmBusinessLayerPlugin - Unhandled Exception caught in plugin startup.System.TypeInitializationException: The type initializer for 'SolarWinds.NCM.Transport.ConfigArchive.ConfigTransfer' threw an exception. ---> System.IO.FileNotFoundException: Could not load file or assembly 'SolarWinds.Ncm.IoC, Version=, Culture=neutral, PublicKeyToken=null' or one of its dependencies. The system cannot find the file specified.
   at SolarWinds.Cirrus.BusinessLayer.NCMServiceContainer.CreateContainer()



  • Network Configuration Manager (NCM) 7.7


DCE component was not registered correctly


Examine the Windows Registry on each server (Main Poller, Additional Poller, and HA component):

  • Verify that the following value exists with the string entry named "DCE"
  • Verify that the value is <installation dir>\Orion\DCE. By default, this is C:\Program Files (x86)\SolarWinds\Orion\DCE\.




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