In the last few weeks, I’ve received an increasing number of messages from people asking about how they can stop annoying pop-up ads that appear on their PCs without any warning. These ads aren’t like regular Web pop-ups. Instead, they look like dialog boxes, with the words “Windows Messenger” in the title bar.
Here’s what’s going on. The Messenger service (no relation to the instant-messaging utilities used by MSN, AOL, and Yahoo) was originally designed for network administrators and programs to send messages over a corporate network. A printer could pop up a window telling you you’re out of paper, or your IT guy could alert you that he’s about to shut down a file server for emergency maintenance.
Although this capability has been in Windows NT and Windows 2000 for years, sleaze merchants only recently discovered this service. The same clowns who sell bulk-mailing software now sell software that can tap directly into your Internet connection and use the Messenger service (a component of Windows, not be confused with the Windows Messenger instant messaging program) to spam you with these ads.
Because these messages look like legitimate Windows dialog boxes, they have the potential to fool users who haven’t heard about this trick. It’s a gross invasion of your privacy, and it ought to be illegal. Utilities designed to stop pop-ups spawned by Web sites will have no effect on these messages. Fortunately, you can block these jokers with any of the following strategies:
- Use a hardware router or a software firewall. These messages typically arrive on ports 135, 137, or 139. By default, a good firewall will block unsolicited requests on any of these ports.
- Turn off the Messenger service. Using Windows 2000 or Windows XP, open Control Panel and find the Services icon. (It’s in the Administratifve Tools folder, under the Performance and Maintenance category.) Find the entry for Messenger, double-click, and click Stop. Then change the startup type to Disable.
You can read more about this topic and download a free utility that will automate the process of disabling this service at the
Stop Messenger Spam site.