I bought a book at google play before I changed the Adobe ID password. After the password changed I downloaded the acsm file of the respective book from google play. When I open the acsm file with Adobe Digital Editions 4.5 I get the error message "Error ! Check activation".
I checked the activation and it seems to be okay. I reinstalled Adobe Digital Editons 4.5 but it was no help.
Finally I deactivated the Computer and activated again my Adobe ID. Adobe Digital Editons confirmed the activation and the activation status seems okay.
I repeated the download of the acsm file from google play.
However the "Error ! Check activation" message still remains when opening the acsm file with both the first downloaded file and the file downloaded after the new installation of Adobe Digital Editions and the newly activation of the computer.
I'm grateful for any help on this.