A proxy device intercepts requests from client devices to access message data through a message data device, such as accessing e-mail messages through a mail server implementing post office protocol (POP) or other messaging protocol. The proxy device determines to authenticate of a client device when, for example, the client device, is located within certain areas that differ from a geographic region associated with a message account holder. Authentication of the client device may include collecting additional information, such as a universal identifier that may be used by the client device to access various services. The proxy device may further forward a notification message to the client device indicating the access to the message data is pending until the client device is authenticated. If the client device is successfully authenticated, the proxy device forwards the request to the message data device to enable the client device to access the message data.