[davidfor]

Originally Posted by Grant Jacobs

Thanks, I find the whole ASCM business very confusing an unclear. And still do, I'm sorry.

I take you're saying that Google Play communicates with ADE to add/check license keys. I can't see anything in the Google Play user account that lets me see or edit this to verify what it thinks it's stuffing into the ACSM files.

No, that is not what I am saying. I don't know the exact details, but, Google probably talks to Adobe and generates a license for the book. You download the ACSM file and open it with ADE. ADE confirms the license and adds it to you account. Or maybe they generate a decryption key unique to the book and your account.

Your original error message looks like something that should have been transient. Downloading the ACSM and opening it in ADE should hopefully work. I'm pretty sure I have seen this in the past, and the next time I tried it, everything was OK.

Looking on the ADE website, it gives me one email address, the one I expected because it's the one I nicknamed email-computer@gmail.com that the ADE app tells me authorises my computer.

If I have more that one account where are these? I can't see anything on the ADE site indicating that I have another account, and I can't understand how I could anyway as I only have one book reader. Why would I register another account?

The main reason people register another account is if they forget the previous one, or if they lose access to it in some way. Losing access to the email address the account is registered to is a common reason.

I've also tried dragging the ACSM file to the Kobo desktop app in the hope that it'd sort it out, but app doesn't even try.

The Kobo desktop application does not handle books with Adobe DRM at all. You need ADE to do this.