Running Ventrilo as administrator in Vista fix some issue that people reported, for example : Key binding not working when in game.
- Right click on the Ventrilo client shortcut icon.
- Select "Properties" at the bottom of the list.
- Then this window will appear.
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- Select the "Compatibility" tab at the top.
- Select the box next to "Run this program as an administrator."
- Then click "Apply".
- Then click "OK".