Failed to open

[Arason]

I am new to Calibre.

Can anyone help or lead into a direction to understand what is going on?

Thanks,
Andy

calibre, version 6.13.0
ERROR: Loading book failed: Failed to open the book at C:\Users\Andy\Calibre Library\Unknown\CR!GV5YSBJY515091RFJRDCMC8KY4CG.az w (12)\CR!GV5YSBJY515091RFJRDCMC8KY4CG - Unknown.md. Click "Show details" for more info.

Failed to convert book: C:\Users\Andy\Calibre Library\Unknown\CR!GV5YSBJY515091RFJRDCMC8KY4CG.az w (12)\CR!GV5YSBJY515091RFJRDCMC8KY4CG - Unknown.md with error:
InputFormatPlugin: TXT Input running
on C:\Users\Andy\Calibre Library\Unknown\CR!GV5YSBJY515091RFJRDCMC8KY4CG.az w (12)\CR!GV5YSBJY515091RFJRDCMC8KY4CG - Unknown.md
File extension indicates particular formatting. Forcing formatting type to: markdown
Language not specified
Creator not specified
Building file list...
IgnoreFile('Could not read from file: C:\\Users\\Andy\\AppData\\Local\\calibre-cache\\ev2\\t\\c0-kmfyivfu\\"��H�I eGpl� \x17���ֱ=0\x0e�ڂ�g���r�\x10K�ت���w6 with error: [Errno 22] Invalid argument: \'C:\\\\Users\\\\Andy\\\\AppData\\\\Local\\\\calib re-cache\\\\ev2\\\\t\\\\c0-kmfyivfu\\\\"��H�I eGpl� \\x17���ֱ=0\\x0e�ڂ�g���r�\\x10K�ت���w6\'')
IgnoreFile('Could not read from file: C:\\Users\\Andy\\AppData\\Local\\calibre-cache\\ev2\\t\\c0-kmfyivfu\\�H�� ����\x15���E�N�\x07\x07�5MQ\'3Yb�Ժ�.\u07be��r��֭Z5 58��XZK�� with error: [Errno 22] Invalid argument: "C:\\\\Users\\\\Andy\\\\AppData\\\\Local\\\\calibr e-cache\\\\ev2\\\\t\\\\c0-kmfyivfu\\\\�H�� ����\\x15���E�N�\\x07\\x07�5MQ\'3Yb�Ժ�.\\u07be��r� �֭Z558��XZK��"')
Failed to run pipe worker with command: from calibre.srv.render_book import viewer_main; viewer_main()
Traceback (most recent call last):
File "runpy.py", line 196, in _run_module_as_main
File "runpy.py", line 86, in _run_code
File "site.py", line 83, in <module>
File "site.py", line 78, in main
File "site.py", line 50, in run_entry_point
File "calibre\utils\ipc\worker.py", line 196, in main
File "<string>", line 1, in <module>
File "calibre\srv\render_book.py", line 821, in viewer_main
File "calibre\srv\render_book.py", line 812, in render_for_viewer
File "calibre\srv\render_book.py", line 789, in render
File "calibre\ebooks\oeb\iterator\book.py", line 62, in extract_book
File "calibre\customize\conversion.py", line 242, in __call__
File "calibre\ebooks\conversion\plugins\txt_input.p y", line 310, in convert
File "calibre\ebooks\conversion\plugins\html_input. py", line 90, in convert
File "calibre\ebooks\conversion\plugins\html_input. py", line 153, in create_oebbook
File "calibre\ebooks\html\input.py", line 287, in get_filelist
File "calibre\ebooks\html\input.py", line 265, in traverse
File "calibre\ebooks\html\input.py", line 109, in __init__
ValueError: embedded null character

[jhowell]

It looks like you have added an unusable file to calibre. Calibre expects the file extension .md to be in Markdown format but Kindle for PC uses that extension to hold metadata for books in KFX format.

If you are trying to add books downloaded using Kindle for PC it only works for specific older versions of that app and only for books published prior to this year. See this thread for more information.