New Windows 10 installation, new ADE 4.5.1 installation.
Bought book from my local bookseller's website, downloaded URLLink.acsm
Opened ADE, dragged URLLink.acsm on ADE window.
Dialog Box "Computer Authorization" pops up.
Enter credentials that work for the Adobe ID web portal and press "Authorize"
The following error message appears:
Please advise how I can use ADE to open the book I have purchased.
Ok, I found the cause of the problem: a wrong system time in my windows installation caused the problem. Windows has been using the wrong time (1 hour off) despite having "set time automatically" enabled and having the correct time zone set. Manually setting the correct time fixed the problem. Kudos to the Adobe knowlegebase for the correct answer ( Lösung für den Fehler: REQUEST_EXPIRED in Digital Editions ), maybe it would be helpful to add this information to the database for the support chat.