diff --git a/scripts/test_apache2.sh b/scripts/test_apache2.sh
index 803385e43..65f514d65 100755
--- a/scripts/test_apache2.sh
+++ b/scripts/test_apache2.sh
@@ -36,6 +36,6 @@ fi
 
 # run letsencrypt-apache2 via letsencrypt-auto
 cd letsencrypt
-letsencrypt-auto -v --debug --text --agree-dev-preview --agree-tos \
+./letsencrypt-auto -v --debug --text --agree-dev-preview --agree-tos \
                    --renew-by-default --redirect --register-unsafely-without-email \
                    --domain $PUBLIC_HOSTNAME --server $BOULDER_URL