I had installed ADE 4.0.3. yesterday on a Windows 8.1. laptop and it functioned fine with transferring both existing library and with downloading books from an ebook store. After downloading ebooks from a public library today, ADE stopped working properly. The screen is half-empty, only a few function buttons are accessible, and virtually none actually does work. I get an error message that the system is trying to fix the problem, and that I will be notified once a solution has been found. De-installing and re-installing ADE did not help; I tried installing on a second computer (Windows 8), and the same problem occurred. Now, nothing works. Does anyone have a solution to this problem?