Problem(s) Encountered:

Error message in the prospero window indicating communication was lost with the sequencer, IC, or the HE on the telescope.  Could not find a description in any of the documents how to restore the communication from the IC  alone.  Restarted the IC but it hung every time.

Solutions:

Power-cycled the HE.  IC started fine after that.  Brought up the rest of the TCS and the data system.