We've created this Forum Thread with some workarounds and advice to assist you in publishing you ebook.
erros for my epub with atlantis
hi here is the errors please help me!!!!
make it with atlantis word procesor
ERROR: Publisher value is missing in Ops/content.opf
ERROR: Unable to locate a valid publication date. A date with the event attribute publication (opf:event=publication) is required in Ops/content.opf
ERROR: Unmanifested file: META-INF/calibre_bookmarks.txt