[koland]

I have two versions of a book, one a PRC and the other epub. Calibre won't open either one, nor do any conversion. I haven't tried another mobi reader, but I can open the epub using Nook for PC. I'm fairly certain that the epub was created via PubIt (there is no DRM on either, or isn't supposed to be). With a couple thousand books, I haven't run into this before.

This is the error I get trying to open the PRC:

calibre, version 0.7.47
ERROR: Could not open ebook: Unknown book type: '\x00BOOKMOB'

Traceback (most recent call last):
File "site-packages\calibre\gui2\viewer\main.py", line 62, in run
File "threading.py", line 483, in run
File "site-packages\calibre\ebooks\oeb\iterator.py", line 195, in __enter__
File "site-packages\calibre\customize\conversion.py", line 204, in __call__
File "site-packages\calibre\ebooks\mobi\input.py", line 26, in convert
File "site-packages\calibre\ebooks\mobi\reader.py", line 277, in __init__
MobiError: Unknown book type: '\x00BOOKMOB'


This is the error on the EPUB:
calibre, version 0.7.47
ERROR: Could not open ebook: unpack requires a string argument of length 22

Traceback (most recent call last):
File "site-packages\calibre\gui2\viewer\main.py", line 62, in run
File "threading.py", line 483, in run
File "site-packages\calibre\ebooks\oeb\iterator.py", line 195, in __enter__
File "site-packages\calibre\customize\conversion.py", line 204, in __call__
File "site-packages\calibre\ebooks\epub\input.py", line 137, in convert
File "site-packages\calibre\utils\zipfile.py", line 734, in __init__
File "site-packages\calibre\utils\zipfile.py", line 755, in _GetContents
File "site-packages\calibre\utils\zipfile.py", line 765, in _RealGetContents
File "site-packages\calibre\utils\zipfile.py", line 240, in _EndRecData
error: unpack requires a string argument of length 22


Any suggestions? I tried renaming the .EPUB as .ZIP and opening, but get an error that it isn't a zip file. Yet,the nook app opens it just fine. I just don't want to read it there. Running Calibre 0.7.47