40223 Execution error


I am using two ABB robots with ATI force/torque sensors. Recently, I removed one of the sensors from one robot and I created a new system using system builder. Since then, when I run a simple program just to activate force control, it stops at the very first line, which is FCLoadID command. And I keep getting this error code 40223 which says:

40223, Execution error
The execution of task T_ROB2 has been stopped by a runtime error.
The program execution is immediately halted.
Probable causes
The program error is considered UNRECOVERABLE so no error
recovery attempt by an error handler routine (if used) was allowed. The
actual cause of the error may vary, and is likely to be specified in an
event log message logged simultaneously as this one.
Recommended actions
1) Check other event log messages logged simultaneously to determine
the actual cause.

T_ROB2 is the one with the F/T sensor. Any input will be very much apprecited.

Thank you,