Our books all pass the dreaded ePubCheck3 validation as a rule before they ever go out the door. These same epubs upload fine to other vendors, including the also-dreaded "fruit vendor."
Yet every time I try to upload an epub through NookPress, I get the error "An Unknown Error Occurred" - and that's after I click on "View Details."
Here's the kicker - the book uploads fine when I go through pubit. I've sent multiple emails to firstname.lastname@example.org - the only email address I can find anywhere - and received no response.
If NookPress becomes the only way to publish on the Nook, and pubit goes away, our books won't be available on the Nook, and you can bet we'll let all our readers know exactly why.
That error, while it seems ominous, is actually nothing. Its a glitch. That error became commonplace for quite a while before disappearing right before Pubit became NookPress. It, however, seems to have followed from Pubit. If you give your book 12-24 hours it should go live on BN.