[Tanjamuse]

I don't know what kind of error this is, except that I've never seen it before:

calibre, version 4.1.0
ERROR: Unhandled exception: <b>BusyError</b>:BusyError: database is locked

calibre 4.1 [64bit]  embedded-python: True is64bit: True
Windows-10-10.0.18362-SP0 Windows ('64bit', 'WindowsPE')
('Windows', '10', '10.0.18362')
Python 2.7.16+
Windows: ('10', '10.0.18362', 'SP0', u'Multiprocessor Free')
Interface language: en_GB
Successfully initialized third party plugins: Find Duplicates (1, 6, 3) && Import List (1, 3, 0) && MultiColumnSearch (1, 0, 74) && Favourites Menu (1, 0, 4) && Generate Cover (1, 5, 21) && Count Pages (1, 8, 2) && FanFicFare (3, 11, 5) && Job Spy (1, 0, 159) && Tanja's Tools (0, 0, 8) && Save Composite Custom Columns (1, 1, 0) && Reading List (1, 6, 6) && User Category (1, 5, 3)
Traceback (most recent call last):
  File "site-packages\calibre\gui2\__init__.py", line 484, in dispatch
  File "site-packages\calibre\gui2\actions\choose_library.py", line 590, in switch_requested
  File "site-packages\calibre\gui2\ui.py", line 761, in library_moved
  File "calibre_plugins.tanja_tools.action", line 81, in library_changed
  File "calibre_plugins.tanja_tools.action", line 88, in rebuild_menus
  File "site-packages\calibre\db\legacy.py", line 82, in __init__
  File "site-packages\calibre\db\legacy.py", line 47, in create_backend
  File "site-packages\calibre\db\backend.py", line 434, in __init__
  File "site-packages\calibre\db\backend.py", line 622, in initialize_custom_columns
  File "site-packages\calibre\db\backend.py", line 874, in execute
  File "c:\t\t\apsw-tti2z1cq\src\cursor.c", line 236, in resetcursor
BusyError: BusyError: database is locked

All I did was switch from one library to another.

I have 16 gb RAM