Do you have them hidden, or have you shrunk them down off of the screen? Try holding your pointer over where they would normally be, if you see a little arrow pointing up and down, click your mouse and move it up a bit. If the taskbar pops up when you put your mouse over where it should be, you're just hiding it. This can be changed by right clicking on it after you highlight it, clicking properties, then just uncheck the "Auto-hide the taskbar" option.
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