I got a problem converting epub books to mobi on Calibre 0.7.45.
Simply put, I got an error log like this:
Parsing all content...
Manifest item u'Robert A. Heinlein - La Luna \xe8 Una Severa Maestra_split_000.htm' not found
Manifest item u'Robert A. Heinlein - La Luna \xe8 Una Severa Maestra_split_001.htm' not found
Manifest item u'Robert A. Heinlein - La Luna \xe8 Una Severa Maestra_split_002.htm' not found
Manifest item u'Robert A. Heinlein - La Luna \xe8 Una Severa Maestra_split_003.htm' not found
Parsing titlepage.xhtml ...
Parsing stylesheet.css ...
Property: Unknown Property name. [42:5: text-justify-trim]
Spine item u'Robert_A._Heinlein_-_La_Luna_\xe8_Una_Severa_Maestra4' not found
Spine item u'Robert_A._Heinlein_-_La_Luna_\xe8_Una_Severa_Maestra3' not found
Spine item u'Robert_A._Heinlein_-_La_Luna_\xe8_Una_Severa_Maestra2' not found
Spine item u'Robert_A._Heinlein_-_La_Luna_\xe8_Una_Severa_Maestra1' not found
Python function terminated unexpectedly
Spine is empty (Error Code: 1)
Since I solved it, I'd like to share my experience, just in case someone else stumbles on the same issue.
The problem is that non-standard characters in file names aren't managed properly.
The solution is quite simple, even if it takes some work.
1) Open the epub file with Winzip
2) Rename the offending file names (in this case, the html files) without using strange characters.
3) Edit the file "content.opf" and replace all the occurrences of the file name (I used notepad++, it works well)
4) Update the epub with the new files, that is zip again everything and change the extension from ".zip" to ".epub"
I did this on five ebooks and all of them were then converted with no error.
I don't know if this kind of problem has ever been addressed before (I didn't find anything by forum search), but if it was excuse me for wasting time and space.