diff --git a/prep_code.sh b/prep_code.sh
index 0a3372890d6733722c6d66ef40e0aafc9a0c47c1..1e7672b58be4f333aa8823cfa5f849a8fbdd60d8 100755
--- a/prep_code.sh
+++ b/prep_code.sh
@@ -197,7 +197,7 @@ if [ -n "${mnh_expand_options-}" ]; then
   for rep in $reps; do
     if [ -d $rep ]; then
       #find $rep -type f | while read file; do
-      find $rep -type f -not -name '.*.swp' | while read file; do
+      find $rep -type f -not -name '.*.swp'  -not -name '.*.swo' | while read file; do
         apply_mnh_expand "$file"
       done
     fi