Originally Posted by jackie_w
It's possible that's your problem, then. If you're doing it via Sigil, I expect Sigil does some automatic opf-tidying-up as you remove chunks and save the changes. But I don't know it well enough to know in detail exactly what it does and doesn't clean up.
The <manifest> is a list (id, url, media-type) of all the files in the epub,
the <spine> is an ordered list of ids of the html files which will be displayed when you read the epub,
and the <guide> is... I'm not sure what it's purpose is in an epub but I think the items in there are used by Kindle formats.
OPF (section) Cleanup does not always
get done... Unless:
Manifest: you move an existing file. (you can move it back after a move)
Spine: rename the file
Guide: assign a semantic to a different file