can't find and open upload books

[Всеволод]

i can't find in amazonkindle book upload books. They are marked as uploaded and add to the library, although they can't be open in calibre too(other reader-programms which open fb2 files work). There is such bug report:
Traceback (most recent call last):
  File "site-packages\calibre\gui2\viewer\main.py", line 40, in run
  File "threading.py", line 504, in run
  File "site-packages\calibre\ebooks\oeb\iterator\book.py", line 99, in __enter__
  File "site-packages\calibre\customize\conversion.py", line 239, in __call__
  File "site-packages\calibre\ebooks\conversion\plugins\mobi_input.py", line 40, in convert
  File "site-packages\calibre\ebooks\mobi\reader\mobi8.py", line 70, in __call__
  File "site-packages\calibre\ebooks\mobi\reader\mobi8.py", line 382, in expand_text
  File "site-packages\calibre\ebooks\mobi\reader\markup.py", line 301, in expand_mobi8_markup
  File "site-packages\calibre\ebooks\mobi\reader\markup.py", line 45, in update_internal_links
  File "encodings\utf_8.py", line 16, in decode
UnicodeDecodeError: 'utf8' codec can't decode byte 0xd0 in position 60306: invalid continuation byte

calibre 0.8.70
windows xp sp3

[Kovid Goyal (kovid)]

That error indicates the KF8 part of that file is corrupted. calibre
(and the Kindles) will use the KF8 aprtin preference to the MOBI part,
which is why both will not work. You will need to get this file from
annother source.

 status invalid