Calibre 5.3 Not Starting on Win 10

[serpah]

Hello, I've been using Calibre for some time and had a very old version. I recently upgraded to 5.2 and then to 5.3 and Calibre stopped working. It crashed just after initializing the interface. I have removed Calibre completely and reinstalled and I still get the same error message from calibre-debug, pasted below.

I'd appreciate any assistance!

Spoiler:

calibre 5.3 embedded-python: True is64bit: False
Windows-10-10.0.18362-SP0 Windows ('32bit', 'WindowsPE')
32bit process running on 64bit windows
('Windows', '10', '10.0.18362')
Python 3.8.5
Windows: ('10', '10.0.18362', 'SP0', 'Multiprocessor Free')
Interface language: None
Turning on automatic hidpi scaling
devicePixelRatio: 3.0
logicalDpi: 96.0 x 96.0
physicalDpi: 92.1829931972789 x 92.36363636363636
Using calibre Qt style: True
[0.00] Starting up...
[0.00] Showing splash screen...
[1.38] splash screen shown
[1.38] Initializing db...
[1.48] db initialized
[1.48] Constructing main UI...
Traceback (most recent call last):
File "calibre\gui2\library\views.py", line 972, in database_changed
File "calibre\gui2\library\views.py", line 831, in restore_state
File "calibre\gui2\library\views.py", line 734, in apply_state
File "calibre\gui2\library\views.py", line 689, in apply_sort_history
File "calibre\gui2\library\views.py", line 573, in sort_by_named_field
File "calibre\gui2\library\views.py", line 532, in sort_by_column_and_order
File "calibre\gui2\library\models.py", line 510, in sort
File "calibre\gui2\library\models.py", line 518, in _sort
File "calibre\db\view.py", line 265, in incremental_sort
File "calibre\db\view.py", line 249, in multisort
File "calibre\db\view.py", line 244, in _do_sort
File "calibre\db\cache.py", line 63, in call_func_with_lock
File "calibre\db\cache.py", line 978, in multisort
TypeError: '<' not supported between instances of 'str' and 'float'

[kovidgoyal]

Can you attach the metadata.db file from your calibre library folder.

[serpah]

See attached

[kovidgoyal]

That database somehow has empty strings for the series index, and with the update to python 3 in calibre 5, sortingit errors out. Will add a fix fo rth enext release, in the meantime you can downgrade calibre to 4.23

[serpah]

Got it! Thank you for looking into this, and a belated happy birthday!