Skip to main content

In UNIFI, after switching LCs, there is no communication with the ACQUITY LC - WKB7860

Article number: 7860


  • In UNIFI, the ACQUITY LC is not responding
  • Communication error for LC
  • In the instrument console, the blue-green circle at each LC component does not go away




The IP addresses assigned by the DHCP server are not the same ones assigned in UNIFI Device Management. 


  1. Exit the UNIFI portal.
  2. Clear all components from the Waters DHCP Server Cofiguration.exe located in [installed-drive]:\Program Files\Waters\UNIFI\Server\Bin on the workstation/LND.
  3. Stop the WatServiceHost under services in Task Manager (right-click on the task bar and select Task Manager to open it). Wait for all eight processes to close for a workstation. This must be done on the LND for a workgroup. 
  4. Stop the Waters DHCP server under services in Task Manager
  5. Power-off the ACQUITY. (Do NOT power it back on.)
  6. Start the DHCP server under services in Task Manager.
  7. Start the WatServiceHost under services in Task Manager. For a workstation, wait for all eight processes to start up. 
  8. Log in to the client.
  9. In Device Management, go to the Instrument Systems tab.
  10. Right-click on the system that is online and select Change status > Offline.
  11. Right-click on the system that is online and select Change status > Decommission.
  12. Right-click on the system and select Delete Instrument System.
  13. Do this for any system that is using the ACQUITY components that have "bad" IP addresses.
  14. Under the LND or Workstation, select the Manage Instruments tab at the bottom.
  15. Select each ACQUITY component and select remove. Repeat until all components are gone.  
  16. Go to the Manage Drivers tab.
  17. Remove each of the ACQUITY drivers.
  18. Add back in the drivers that are needed.
  19. Power-on the ACQUITY.
  20. Ensure that the IP addresses in the UNIFI Manage Instruments tab agree with the IP addresses in the external DHCP server.
  21. If the IP addresses agree, create a new instrument system and bring it online. 




Not able to find a solution? Click here to request help.