Not to be confused with the instant-messaging service with a similar name, Windows Messenger Service is used primarily by businesses to send pop-up text messages to alert users of such events as impending server shutdowns.
Service Pack 2 for Windows XP, which is expected by the middle of next year, will turn off the service by default. Current editions of Windows XP have it enabled.
Windows Messenger Service has been exploited by spammers, and security vulnerabilities that can be exploited by attackers have been recently noted by Microsoft. Several security analysts have urged home and small business users who don't need the service to turn it off to prevent attacks.
Over the past two weeks America Online has also taken the unusual step of disabling the service for its subscribers.