I'm having the same problem since my"upgrade" to Windows 10. I've combed all of the posts on these forums and have seen posts referring to this problem dating back to 2011. It's frustrating and infuriating. It's apparently impossible to contact Adobe directly about the problem and it would appear that no one from Adobe ever looks at these posts. I liked the suggestion I saw that this is a plot by Adobe and e-book sellers to prevent borrowing from libraries.The problem exists only for e-book reader users. I was told by my local library that newer tablets don't require ADE to download from public libraries.