Widget Problem

I’m using widgets and want to put different sidebars on the index.php, single.php, and archives.php page. No problem — I created multiple widget sidebar and now have three.

But if a widget (like categories) is being used in sidebar 1, and can’t also use it in sidebars 2 or 3. How can I set it so that I can have a widget used in the other sidebars too?