Thought this program might be useful.
Basically you run it and you can reorder your taskbar buttons, just by draggin and dropping.
From the website:
"No hotkey, no extra steps, drag and drop the programs on your Windows taskbar by simply... well, dragging and dropping them! Neat concept, huh?
No need to get all nervous when a program crashes or if you wanna reboot; you can re-order your programs exactly as they were."

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