Unable to downbload - Error getting license. E_Google_Device_Limit_reached

I received in my email an eBook (as an acsm file) as a present. I'm trying to use Adobe Digital Editions to convert it into en ePub. However, I get this error message:

Unable to downbload. Error getting license. License server communication problem: E_Google_Device_Limit_reached.

How can I circumvent this error?