Two things to check ~ I'm not at all convinced either will help, though, but can't think of anything else.
Double-check the time and timezone on your computer and the Kobe reader.
There are lots of bugs in ADE2.0. 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
Thank you for your help but unfortunatly none of them worked...I uninstalled ADE 2.0 and use 1.7.2 but even though all the authorisations are ok I stil get the same message...
One question: how can we unauthorise an ID on 1.7.2? I tried to do what seems to work sometimes with ADE 2.0, to "reset" the authorisation, reboot the program and start it again but couldn't find that option on 1.7.2...
One (last) question: do you think that if I create a new ID with a different email and change the ancient authorisation for the new one on my PC I would have a chance to download my ebooks?
ctrl-shift-D (cmd-shift-D on Mac) also works to deauthorize on 1.7.2.
(I haven't tested it as I don't wnat to deauthorize, but I have verified that at least it brings up the prompt 'do you want to deauthorize', so I guess it will work..)
I can't think of any other suggestions, I am afraid.