To delete an image contained within the library navigate to the “Image Management” through the “Asset Library” link on the Header Bar.

You will be presented with the following screen:

 

Select the image that you would like to delete by clicking on the item using the left hand mouse button. The right hand frame of the browser will be populated with a “File Details” property page containing the details of the image selected:

 

 

To delete the item click the “Delete File” button.  You will then be asked to confirm your choice:

 

 

Click OK and the image will be deleted and the tree menu will be refreshed.