C# Enemy Combat System 'PlayerHealth' Error, help needed

Here is a picture of the error http://i.imgur.com/uXtALCG.png

Here is a picture pf the code http://i.imgur.com/wO3jRm3.png

If you can help thanks so much

Unity can’t find any declaration of the class of PlayerHealth.
Are you sure this class is available in your project? In the global namespace?

According to your code, it’s not EnemyHealth instead of PlayerHealth?