Whether "FORTRAN STOP" at step 2.4.2 running pair is an error

Dear I-TASSER Discussion Board,
Whether "FORTRAN STOP" at step 2.4.2 running pair is an error?

1. make seq.txt and rmsinp
2.1 run Psi-blast
2.2 run psipred
2.3 run solve
2.3 run solve
2.4 run pairmod
2.4.1 removing homology templates based on real and 1
2.4.2 running pair ................
FORTRAN STOP
3.1 do threading
start threading QQQ