The automatic probe changer (APC) rack could not be lowered.
As a result, a command was executed, which required the APC rack to be lowered, and it could not be lowered.
What you should do:
You should check the command's definition and correct the measurement routine.
Correct the problem with the APC racks lower/raise capability.
If the error reoccurs, contact your Giddings & Lewis service representative.