Why is Lt not communicating with the PowerLab for recording data?

One possible cause for this issue is a corrupted install of the Kura Desktop App.  To solve this problem, uninstall the Kura Desktop App, open a course in your ADInstruments Lt instance, and click the button to record data from PowerLab to initiate the download of the newest version of the Kura Desktop App.  
If this does not solve the issue, please contact your local ADInstruments Technical Support for assistance.