Further to several trials, I am definitely unable to access to a PDF file since an unsollicited update with MAC. I tried to delete the OOBE folder in compliance with the recommendations. However, unfortunately, the application Acrobat licensing has stayed there. It does not work and my screen remains blank.
For licensing related issues, it's best to contact Adobe's support directly. I had a problem recently when Acrobat insisted on my trial period having expired, even though I have a valid license. Something got messed up on my computer, and customer support walked me through the steps to fix it.