I was trying to open a DRM protected ebook in ADE 4.5.2 on Android 6.0.1. The activation seemed to work, at least there has not been any error message.
When I try to open an acsm file (which worked without problems on another android 6 device before), an error occurs like (translated from German):
"Failed to connect to Fulfillment-server. Make sure you are connected to the Internet"
My Internet works fine. I tried to deactivate old accounts, without success.
What can I do?
Has you check if your Secury Software anything blocked?
Yes I did. No firewall is blocking anything as far as I can see.
Have you try Digital Edition add as secure program in the Firewall?