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I'm trying to authorize my laptop so I can download eBooks.  I lost the id number a year or so ago. So when I try and create an ID, I get the above message. Adobe suggested editing the registry, but their suggestion didn't work. I was given this link; https://helpx.adobe.com/digital-editions/using/authorizing-and-de-authorizing-adobe-digital-editions.html , but as I haven't got the sign-in details, I cannot follow this procedure. Removing/reinstalling Digital Editions also doesn't work. Any ideas would be appreciated, thanks.