[njhow]

Hi
This is my first post and I hope that I can get some help.

I have a Kindle Paperwhite (New Xmas 2019).
Calibre is up to date 4.14
My PC is Windows 10
Connect Paperwhite to PC via a USB hub.

I get message "Error communicating with device "

Screen shot of message

Traceback (most recent call last):
File "site-packages\calibre\gui2\device.py", line 90, in run
File "site-packages\calibre\gui2\device.py", line 543, in _sync_booklists
File "site-packages\calibre\devices\usbms\driver.py", line 459, in sync_booklists
File "site-packages\calibre\devices\usbms\driver.py", line 457, in write_prefix
File "site-packages\calibre\ebooks\metadata\book\json_codec.p y", line 136, in encode_to_file
File "json\__init__.py", line 251, in dumps
File "json\encoder.py", line 210, in encode
MemoryError

I hope that someone can help me.
Thanks