To troubleshoot an instrument communications error proceed as follows:
In ATD (or ATS) software, go to "Tools" > "Options" > "Instruments".
Clear the check marks that enable the instruments (just scanner in ATD).
Reset the scanning head.
Press and hold the scanner's measure button (about 5 seconds) until it turns red.
Return to "Tools" > "Options" > "Instruments": restore the check marks and then click on "Apply".
If communications is restored to the scanner, continue by performing a FULL track and scanner calibration.
This should solve the problem. If it fails to resolve the issue, run 'Instrument Diagnostics' in the ATD / ATS software and see if it shows up there. If it does not, contact X-Rite's support staff.