I've used ADE to download e-books from my public library onto my Kobo for over a year now but for a week now I haven't been able to. When I open the library book, select 'download' and it opens ADE but it is a totally blank page (there should be several books there that I have purchased). It sits on this blank screen for a while and eventually an error message comes up "ADE 2.0 has stopped working. A problem caused the program to stop working correctly. Windows will close the program and notify you if a solutions is available".
I pinged my local library who suggested that I uninstall ADE and reinstall it. I did that and nothing changed. I waited 24 hrs and tried again. Still no change. I've also removed my computer authorization (ADE-Help-Contr Shift d) and reauthorized. Still can't load a book.
There are lots of bugs in ADE2.0 (and 2.0.1).
Some of them just appear like that for no obvious reason on previously working systems.
Try replacing ADE2.0 with the older but more reliable v1.7.2.
(You can have them both installed at once if you like.)
Version 1.7.2, it is a little difficult to find, available on Adobe site for Windows and for Mac.
The forum software is sometimes corrupting the link above. There shouldn't be a blank in 'editio ns.html'. The following redirects to the same page: http://tinyurl.com/diged172
Some people have found ADE trying to upgrade automatically.
It appears (not 100% sure) that if you install ADE2.0 as a new install (not as an upgrade) that your 1.7.2 will continue to run.
Probably best to say no if 2.0.x installation asks if you want to migrate your library.