When get you the error?
I have the same problem. Trying to authorize Aldiko app on a brand new Anroid telephone. The Adobe ID is valid - OK for logging in at adobe.com. COME ON ADOBE - there are several questions in this very forum during 2013 and NO answers about what to do about the message:
"Failed to authorize device [E_ACT_CERTIFICATE_SYNTAX]" !!!!
Some people have found that the Bluefire app will register your Adobe ID more reliably than Aldiko,
Not sure why, doesn't apply to everyone.