Webmail Messenger uses SMS Text messages for two factor authentication.
The SMS queue shows the SMS Text messages sent by the gateway which are not yet handled by the configured remote SMS transport.
If an SMS Text message cannot be delivered, the “Last Error” column should provide information on why it cannot be delivered. An SMS transport must be configured before SMS Text messages can be sent.
The SMS gateway is used for two factor authentication. A two factor authentication token is only valid for a short time. SMS text messages which are not delivered within 5 minutes are automatically deleted from the SMS queue.