The CNC has tried to include the master axis of an active coupling or that of a Gantry pair in the channel configuration (#CALL or #SET). When including the master axis, the CNC also includes the slave axis which can never occupy one of the main three positions of the channel. The CNC issues an error because there is no free position other than the main three axis.

In order to only include the master axis, the active coupling must be deactivated first (#UNLINK) or undo the Gantry pair. In order to include both the master and the slave axis, first eliminate another axis from the channel or increase the number of axes of the channel.