diff --git a/SRC/pdtrord.f b/SRC/pdtrord.f
index 63e9457a..27eb86fd 100644
--- a/SRC/pdtrord.f
+++ b/SRC/pdtrord.f
@@ -1083,6 +1083,10 @@ SUBROUTINE PDTRORD( COMPQ, SELECT, PARA, N, T, IT, JT,
                ELSE
                   FLOPS = 0
                END IF
+*
+*              Skip update part for current WINDOW if NWIN = 0.
+*
+               IF( NWIN.LE.0 ) GO TO 295
 *
                IF( FLOPS.NE.0 .AND.
      $              ( FLOPS*100 ) / ( 2*NWIN*NWIN ) .GE. MMULT ) THEN
diff --git a/SRC/pstrord.f b/SRC/pstrord.f
index 6960914a..33f23240 100644
--- a/SRC/pstrord.f
+++ b/SRC/pstrord.f
@@ -1083,6 +1083,10 @@ SUBROUTINE PSTRORD( COMPQ, SELECT, PARA, N, T, IT, JT,
                ELSE
                   FLOPS = 0
                END IF
+*
+*              Skip update part for current WINDOW if NWIN = 0.
+*
+               IF( NWIN.LE.0 ) GO TO 295
 *
                IF( FLOPS.NE.0 .AND.
      $              ( FLOPS*100 ) / ( 2*NWIN*NWIN ) .GE. MMULT ) THEN