I have had 5 emails over the last 15 years. I know for sure that I have purchased books on 2 of them. My collection of books works (mostly) on all my devices. Mac, iPad and Sony reader. I started out with the Sony store which shifted to Kobo.
1 of my devices is authorized to my current email account, the other 2 are authorized to my last email account. Except for recent purchases through Kobo, I cant say for certain where the books were purchased. I think the Sony store may have directed us to particular vendors but managed the payment and media download. So I have all these devices working all but one of my books. That one says it is authorized to a different user.
I haven't used a reader for a long time so my guess would be the last two emails are relevant and maybe a third since I have one book that wont work anywhere.
I have two questions:
How is it that substantially all of my content works on all devices even though they are authorized with different email accounts?
Is it possible to get my one book fixed somehow? I don't know which email account it was on but since it doesn't work with any of the devices, it might be my third last email.