[kidkaroo]

While loading a .pdf file, Calibre became unresponsive. Afterwards, I could no longer access any of my .pdf files via Calibre, and all metadata/covers for epub and mobi disappeared.
I’ve tried restoring the database, as well as deleting and rebuilding it. I’ve uninstalled Calibre and then updated to 1.28.0, and rebooted several times. However, Calibre does not show any of my .pdf files, and I’m unable to add any new .pdf files either, although, all these files are in the Calibre library file.

I get the following messge when I try to add a .pdf - ERROR: Cannot view: has no available formats.

I’m able to add epub/mobi files, but after downloading metadata and covers I get the following error message.

calibre, version 1.28.0
ERROR: Permission denied: Could not change the on disk location of this book. Is it open in another program?

Traceback (most recent call last):
File "site-packages\calibre\gui2\metadata\single.py", line 475, in apply_changes
File "site-packages\calibre\gui2\metadata\basic_widgets.py", line 1087, in commit
File "site-packages\calibre\db\legacy.py", line 707, in set_cover
File "site-packages\calibre\db\cache.py", line 57, in call_func_with_lock
File "site-packages\calibre\db\cache.py", line 1104, in set_cover
File "site-packages\calibre\db\backend.py", line 1335, in set_cover
File "site-packages\calibre\utils\magick\draw.py", line 111, in save_cover_data_to
File "site-packages\calibre\startup.py", line 155, in local_open
OSError: [Errno 13] Permission denied

Any help will be greatly appreciated, thank you.