Taskix is a free utility that allows you to reorder the buttons in your Windows XP taskbar in-place using your mouse. If you have "Group similar taskbar buttons" set, it also works inside stacked groups! Simply extract the files from the ZIP into a folder of your choice and start the EXE.
It is most straightforward to use - simply drag-and-drop the button you want to move - , it is fast and uses very few system resources. You also have the option to configure it to be restarted with Windows. There´s a separate 64 bit version available on the homepage to use with Windows XP 64-Bit or Windows Server 2003 64-Bit.
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