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XP - Disable the Messenger service. Its easy to reverse at a later time if needed.
Windows XP Home
Click Start->Settings ->Control Panel
Click Performance and Maintenance
Click Administrative Tools
Double click Services Scroll
down and highlight "Messenger"
Right-click the highlighted line and choose Properties.
Click the STOP button.
Select Disable or Manual in the Startup Type scroll bar
Click OK

Windows XP Professional
Click Start->Settings ->Control Panel
Click Administrative Tools
Click Services
Double click Services Scroll
down and highlight "Messenger"
Right-click the highlighted line and choose Properties.
Click the STOP button.
Select Disable or Manual in the Startup Type scroll bar
Click OK

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