Oops, sorry, I missed your response.
As the code shows, this is how Calibre saves the metadata:
- Turn metadata into a big JSON string
- Does the file "metadata" exist? Then delete it.
- Write the string to the file "metadata"
That there is that file means that it works sometimes (when there is no file already).
That we get that error means that the deletion process is the problem.
99% of what Calibre is doing is writing files to Android (copying books).
The 1% is things like this metadata.
It looks like this is a bug in filesystem_cache.py
It seems that it can't find the parent of metadata although the file exists.
There were major changes in this file in the last few weeks.
You can try replacing that file with the last version.
https://raw.githubusercontent.com/ko...ystem_cache.py