Spammers have co-opted an administration feature in Microsoft’s Windows operating systems and are using it to bring up intrusive advertisements on Internet-connected computers.

The feature, known as the messenger service, typically lets a network administrator send warnings to users when, for example, a server is scheduled to go down for maintenance. Now some advertisers are using it to send bulk messages to anyone connected to the Internet with an accessible address.

You just gotta love well designed operating systems like this… NOT!