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Here is as clear as you can get the taskbar.
If you are using the default aero theme I can change that for you, using Windows Style Builder and post it here in a zip folder.
If you are using a custom theme you will need to ask the theme maker. It's not cool to change someone else work.
This will be a custom theme and you will need to do 1 of these 2 ways of Enabling custom themes for it to work. Enabling Custom Themes - Windows 7
Or Theme - How to Apply Custom Themes
All I need is a name to call the theme.
Let me know.