This error bit applies only to Gemini GT or GT6 units, and enables the error bit when a motor stall is detected. This error will occur regardless of whether the ESK command is enabled or not.
Issuing a DRIVE1 command will clear this error bit. Check all conditions of the commanded move profile (velocity, acceleration/deceleration rates, direction changes, etc.). If the commanded move profile is too aggressive for the attached load, the motor can stall. Also, check any mechanical devices that are physically connected to the motor (gearheads, leadscrews, etc.) for anything that might inhibit motor motion, or cause the motor to bind.
Check the DSTALL setting and increase the value to make the drive less sensitive to capturing motor stalls.