[igorius]

Here i found an error with pdf-handling:

Device using plugboard pdf POCKETBOOK632 None
Setting metadata in: Ich lerne Segeln : Mit Fragenkatalog zum Segelgrundschein at: /var/folders/ks/vqsqkyls4xl00p586x0_59940000z8/C/calibre_6.3.0_tmp_air5bm5t/iw4myfuicaltmpfmt.pdf
Failed to set metadata for the PDF format of: Ich lerne Segeln : Mit Fragenkatalog zum Segelgrundschein
Traceback (most recent call last):
  File "calibre/utils/podofo/__init__.py", line 36, in set_metadata
  File "calibre/utils/ipc/simple_worker.py", line 255, in fork_job
  File "calibre/utils/ipc/simple_worker.py", line 180, in run_job
  File "calibre/utils/ipc/simple_worker.py", line 119, in communicate
calibre.utils.ipc.simple_worker.WorkerError: Worker failed

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "calibre/customize/ui.py", line 454, in set_file_type_metadata
  File "calibre/customize/builtins.py", line 525, in set_metadata
  File "calibre/ebooks/metadata/pdf.py", line 185, in set_metadata
  File "calibre/utils/podofo/__init__.py", line 40, in set_metadata
Exception: Failed to set PDF metadata in (Ich lerne Segeln : Mit Fragenkatalog zum Segelgrundschein): Traceback (most recent call last):
  File "calibre/utils/ipc/simple_worker.py", line 303, in main
  File "calibre/utils/podofo/__init__.py", line 97, in set_metadata_
podofo.Error: ePdfError_InvalidDataType
File: /private/var/folders/wj/cqy1nsyn4wn94d96btkldt0r0000gn/T/t/podofo-csbnzc9f/src/podofo/doc/PdfMemDocument.cpp Line: 263 Handler fixes issue #49
File: /private/var/folders/wj/cqy1nsyn4wn94d96btkldt0r0000gn/T/t/podofo-csbnzc9f/src/podofo/base/PdfParser.cpp Line: 272 Unable to load objects from file.
File: /private/var/folders/wj/cqy1nsyn4wn94d96btkldt0r0000gn/T/t/podofo-csbnzc9f/src/podofo/base/PdfTokenizer.cpp Line: 589

Hope that helps.