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Metatag - Settings - Settings Tab

1. Go To The Metatags Settings Tab

Go to Admin Menu > Configuration > Search and Metadata > Metatag > Settings.

The settings on this tab will provide the ability to select entire content types to exclude, among other things.

Let's examine the pieces in a bit more detail...

Metatag - Settings - Settings Tab - Master Controls

2. Select Content Types In Master Controls

The Master Controls will allow a permitted user to apply Metatag to specific node, term, and user types.

Just select the entities you would like to add Metatag to and the the rest will be ignored.

Metatag - Settings - Settings Tab - Additional and International Settings

3. Add Additional and International Settings

Additional Settings provides the ability to set a Custom Pager String. This will help a search engine to differentiate between multiple pages that have the same meta tag.

Internationalization Options settings provide the ability to handle i18n integration, translation output, and the enabling of translation logging to Watchdog (a system that logs activity on your Drupal site).

Metatag - Settings - Settings Tab - Advanced Settings

4. Add Advanced Settings

The Advanced Settings provides a host of additional settings that are best left alone if you're not sure what you're doing.

Some of these settings, such as Advanced Permissions, can end up adding a lot of unnecessary overhead into your site. Read each description carefullly before moving ahead with any of them.