I have had alot of experience with this happening (middle of nite phone calls). Terry is correct about shutting the PH9/10 controller off and then restarting, make sure the probe head is aligned as close as possible to the front of the machine. After you restart he controller, reboot the PC and the CMM and start from scratch. Are you using Geopak or GeoMeasure??

Duane Wade
TeleFlex Inc.
Kendallville, In