CalibreDB add on Win10 - missing something?

[necromancyr]

I'm getting the following errors when trying to do a simple calibredb add command in Windows 10. The book gets added, just with no cover or metadata. I feel like something simple is missing - i.e., the python scrips or tools it's trying to use - but not certain how to address it.

Traceback (most recent call last):
  File "calibre\ebooks\metadata\epub.py", line 161, in get_zip_reader
  File "calibre\utils\zipfile.py", line 776, in __init__
  File "calibre\utils\zipfile.py", line 811, in _GetContents
  File "calibre\utils\zipfile.py", line 826, in _RealGetContents
calibre.utils.zipfile.BadZipfile: File is not a zip file

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "calibre\customize\ui.py", line 428, in get_file_type_metadata
  File "calibre\customize\builtins.py", line 195, in get_metadata
  File "calibre\ebooks\metadata\epub.py", line 217, in get_metadata
  File "calibre\ebooks\metadata\epub.py", line 164, in get_zip_reader
  File "calibre\utils\localunzip.py", line 264, in __init__
  File "calibre\utils\localunzip.py", line 240, in _extractall
ValueError: Not a ZIP file

[jhowell]

It looks that the EPUB file you are trying to import has a problem. It may be corrupted somehow. Some types of DRM might also produce this result.

You did not state which version of calibre you are using. The most commonly used DRM removal plugin is not compatible with calibre 5.

[necromancyr]

This was it - a (few) bad ePubs to test things out with. Got it working now! Appreciate the help/pointer - never would have guess that!