The reason is because, while I have Acrobat Pro installed on my PC, I have a license for a 2-PC max, and I generally use it on my other 2 PCs, so I dont wan to have to log out just to view PDFs sent to me via email, which is what I need to do 99% of the time on this PC. Occasionally I will need to edit a PDF, and at that point I'll log out of the other PC and log into CC on this PC....