enable tag in magento 1.9 rwd theme

You are using the RWD theme which does not include Product Tags by default. Here's how to add them to the RWD theme:

Step 1: Copy the tags template files to your theme -go to app/design/frontend/base/default/template/tag -Copy the entire /tag folder to: -app/design/frontend/rwd/default/template note that you may have a custom package instead of 'rwd' and you should have a custom theme name instead of 'default'

Step 2: Add the XML call to your layout open app/design/frontend/rwd/default/layout/tag.xmlchange the following code from:

<!-- Remove all tags functionality from theme layout -->

to:

 <catalog_product_view translate="label">
     <label>Catalog Product View</label>
      <!-- Mage_Tag -->
     <reference name="product.info.additional">
         <block type="tag/product_list" name="product_tag_list" before="-" template="tag/list.phtml">
             <block type="page/html_wrapper" name="product.tag.list.list.before" as="list_before"
 translate="label">
                 <label>Tags List Before</label>
                 <action method="setMayBeInvisible"><value>1</value></action>
             </block>
         </block>
     </reference> 
  </catalog_product_view>

*note that you may have a custom package instead of 'rwd' and you should have a custom theme name instead of 'default'

If you don't know which package/theme you are using you can check in the admin under System->Configuration->Design(left column)->Package(tab) & Theme(tab).

You may need to flush you Magento caches to see the changes. In the admin go to System->Cache Management and flush all Magento caches. Now refresh your website and you should see the tags show up near the bottom of the page below the Upsell Products.