To remove the ability for anyone in the world to pop up messages on your computer, you can disable the Messenger service. Its easy to reverse at a later time if you wish to do so.

 

Windows 2000

1. Click Start-> Settings-> Control Panel-> Administrative Tools->Services
2. Scroll down and highlight "Messenger"
3. Right-click the highlighted line and choose Properties.
4. Click the STOP button.
5. Select Disable or Manual in the Startup Type scroll bar
6. Click OK

Windows XP Home

1. Click Start->Settings ->Control Panel
2. Click Performance and Maintenance
3. Click Administrative Tools
4. Double click Services Scroll
5. down and highlight "Messenger"
6. Right-click the highlighted line and choose Properties.
7. Click the STOP button.
8. Select Disable or Manual in the Startup Type scroll bar
9. Click OK

Windows XP Professional

1. Click Start->Settings ->Control Panel
2. Click Administrative Tools
3. Click Services
4. Double click Services Scroll
5. down and highlight "Messenger"
6. Right-click the highlighted line and choose Properties.
7. Click the STOP button.
8. Select Disable or Manual in the Startup Type scroll bar
9. Click OK

Windows NT

1. Click Start ->Control Panel
2. Double Click Administrative Tools
3. Select Services-> Double-click on Messenger
4. In the Messenger Properties window, select Stop,
5. Then choose Disable as the Startup Type
6. Click OK

Windows 98 & ME

Windows Messenger Service cannot be disabled