Still no joy here. I tried 4 or 5 individual options and the error message was the same.
Code:
calibre, version 5.0.1
ERROR: Modify ePub failed: No ePub files were updated
Modify ePubs
Modifying: C:\Users\David\AppData\Local\Temp\calibre_dj7nyszb\rw5zcx9r_modify_epub\9904.epub
Updating metadata and cover
Mind Games - ERROR: Traceback (most recent call last):
File "calibre_plugins.modify_epub.modify", line 78, in process_book
File "calibre_plugins.modify_epub.container", line 86, in __init__
File "src/lxml/etree.pyx", line 3237, in lxml.etree.fromstring
File "src/lxml/parser.pxi", line 1891, in lxml.etree._parseMemoryDocument
ValueError: Unicode strings with encoding declaration are not supported. Please use bytes input or XML fragments without declaration.
ePub not changed after 0.30 seconds
If I modify line 86 in container.py to change 'r' to 'rb', I don't get the error message but ghod alone knows what else that is breaking.