diff --git a/start.sh b/start.sh
index dd0a362..0649af4 100755
--- a/start.sh
+++ b/start.sh
@@ -35,6 +35,8 @@ if [[ ! -f /app/data/configs/homeserver.yaml ]]; then
     if [[ -z "${CLOUDRON_LDAP_SERVER:-}" ]]; then
         yq eval -i ".enable_registration=true" /app/data/configs/homeserver.yaml
         yq eval -i ".password_config.pepper=\"$(pwgen -1s 12)\"" /app/data/configs/homeserver.yaml
+        # just setting enabled to false is not enough. see https://github.com/matrix-org/matrix-synapse-ldap3/issues/123
+        yq eval -i "del(.password_providers)" /app/data/configs/homeserver.yaml
     fi
 fi