Do you have a PDF file that you would like to attach to a reference already in EndNote?
Steps
You can also go to File > Import or drag and drop a PDF from your computer, or set up the PDF auto import function.
To access the PDF of an article
1. Highlight the reference in your library 2. Click the tab with the PDF icon in the Reference Panel
If you wish to view the PDF in a new, larger window, click the icon in the top left of that frame.