diff --git a/genomix/src/main/resources/scripts/stopnc.sh b/genomix/src/main/resources/scripts/stopnc.sh
index 03ce4e7..3928bb7 100644
--- a/genomix/src/main/resources/scripts/stopnc.sh
+++ b/genomix/src/main/resources/scripts/stopnc.sh
@@ -10,7 +10,7 @@
 fi
 
 echo $PID
-kill -9 $PID
+[ "$PID" != "" ] && kill -9 $PID
 
 #Clean up I/O working dir
 io_dirs=$(echo $IO_DIRS | tr "," "\n")