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Disable balloon tips
http://www.vistaarticles.com/articles/76/1/Disable-balloon-tips
By 
Published on 10/21/2006
 
You can stop them via group policy editor.

Disable balloon tips

1. Start up the group policy editor by clicking on the start button and keying in gpedit.msc and pressing Enter.

2. Expand User Configuration, Administrative Templates and Start Menu and Taskbar.

3. Select Remove Balloon Tips on Start Menu items, right click on it and select Properties.

4. Select Enable and hit OK.

5. Close Group Policy Editor and you are finished.