[gkhenderson]

Here is the full debug output
Microsoft Windows [Version 10.0.19045.2965]
(c) Microsoft Corporation. All rights reserved.

C:\Users\Graham>calibre-debug -g
calibre 6.1 embedded-python: True
Windows-10-10.0.19045-SP0 Windows ('64bit', 'WindowsPE')
('Windows', '10', '10.0.19045')
Python 3.10.1
Windows: ('10', '10.0.19045', 'SP0', 'Multiprocessor Free')
Interface language: None
Failed to initialize plugin: 'C:\\Users\\Graham\\AppData\\Roaming\\calibre\\plu gins\\DeDRM.zip'
Traceback (most recent call last):
File "calibre\customize\ui.py", line 744, in initialize_plugins
File "calibre\customize\ui.py", line 64, in load_plugin
File "calibre\customize\zipplugin.py", line 304, in load
File "importlib\__init__.py", line 126, in import_module
File "<frozen importlib._bootstrap>", line 1050, in _gcd_import
File "<frozen importlib._bootstrap>", line 1027, in _find_and_load
File "<frozen importlib._bootstrap>", line 1006, in _find_and_load_unlocked
File "<frozen importlib._bootstrap>", line 688, in _load_unlocked
File "calibre\customize\zipplugin.py", line 196, in exec_module
File "calibre\customize\zipplugin.py", line 192, in get_code
File "calibre_plugins.dedrm.__init__", line 169
print u"{0} v{1}: Copying needed library files from plugin's zip".format(PLUGIN_NAME, PLUGIN_VERSION)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ^
SyntaxError: Missing parentheses in call to 'print'. Did you mean print(...)?
Successfully initialized third party plugins: Find Duplicates (1, 9, 7) && Generate Cover (2, 2, 0) && Library Genesis (1, 2, 0) && Obok DeDRM (6, 5, 4)
QPA platform: windows
devicePixelRatio: 1.0
logicalDpi: 96.0 x 96.0
physicalDpi: 102.23899371069182 x 102.35820895522387
Using calibre Qt style: True
[0.00] Starting up...
[0.00] Showing splash screen...
[0.14] splash screen shown
[0.14] Initializing db...
[0.16] db initialized
[0.16] Constructing main UI...
Traceback (most recent call last):
File "calibre\gui2\ui.py", line 135, in __init__
File "calibre\gui2\ui.py", line 153, in init_iaction
File "calibre\customize\__init__.py", line 624, in load_actual_plugin
File "importlib\__init__.py", line 126, in import_module
File "<frozen importlib._bootstrap>", line 1050, in _gcd_import
File "<frozen importlib._bootstrap>", line 1027, in _find_and_load
File "<frozen importlib._bootstrap>", line 1006, in _find_and_load_unlocked
File "<frozen importlib._bootstrap>", line 688, in _load_unlocked
File "calibre\customize\zipplugin.py", line 203, in exec_module
File "calibre_plugins.obok_dedrm.action", line 24, in <module>
File "calibre\customize\zipplugin.py", line 203, in exec_module
File "calibre_plugins.obok_dedrm.dialogs", line 30, in <module>
File "calibre\customize\zipplugin.py", line 203, in exec_module
File "calibre_plugins.obok_dedrm.utilities", line 10, in <module>
ModuleNotFoundError: No module named 'StringIO'