As mentioned above, that you are a subscriber of Adobe Export PDF as it is an online service that you can access online as well as through the Adobe Reader DC desktop application using your Adobe I.D and password.
I'm having a bit of a problem with this as well. I cannot access the Adobe Export PDF through the Acrobat Reader DC, which I already have installed. When I click on Export PDF it takes me to a buy screen, even though I have already paid the yearly fee. I have a Mac Airbook, would that be the problem? I can only access online. Thank you!