diff --git a/modoboa_installer/scripts/dovecot.py b/modoboa_installer/scripts/dovecot.py
index 58c58de..965f933 100644
--- a/modoboa_installer/scripts/dovecot.py
+++ b/modoboa_installer/scripts/dovecot.py
@@ -153,7 +153,8 @@ class Dovecot(base.Installer):
                 self.get_file_path("fix_modoboa_postgres_schema.sql")
             )
         for f in glob.glob("{}/*".format(self.get_file_path("conf.d"))):
-            utils.copy_file(f, "{}/conf.d".format(self.config_dir))
+            if os.path.isfile(f):
+                utils.copy_file(f, "{}/conf.d".format(self.config_dir))
         # Make postlogin script executable
         utils.exec_cmd("chmod +x /usr/local/bin/postlogin.sh")
         # Only root should have read access to the 10-ssl-keys.try