diff --git a/backup/index.html b/backup/index.html
new file mode 100644
index 0000000..f923682
--- /dev/null
+++ b/backup/index.html
@@ -0,0 +1 @@
+This directory must be writable by the webserver user.
\ No newline at end of file
diff --git a/smartoptimizer/cache/index.html b/smartoptimizer/cache/index.html
new file mode 100644
index 0000000..f923682
--- /dev/null
+++ b/smartoptimizer/cache/index.html
@@ -0,0 +1 @@
+This directory must be writable by the webserver user.
\ No newline at end of file