No valid license for the book

[Granma Rina]

I have just bought a Hanvon ereader and it has adobe digital editions. I have authorised it as a device on my adobe digital editions on my computer and correctly transferred the book to my device but when I try to open it I get the message "no valid license for the book". Can anyone help me as this is the 2nd ereader I have tried with adobe digital editions and I haven't yet been able to read a library book on either one. My ereader is on the adobe supported devices list, it is a Hangwang Pty Ltd Wise reader N520.

[Granma Rina]

I want to add to this, after searching and reading many posts on this forum I have now checked the item info for the epub books I downloaded from my regional library and they say the followiing:

Reading allowed on any device until 31/3/2014

Copying not allowed

This is frustrating as our regional library recommends download with Adobe Digital editions for reading books on any ereader device. Can anyone tell me how I can download direct to my ereader so I am not trying to copy from ADE on my pc to my ereader. I am desperate to get this sorted out.