[hfrummer]

I am having the same symptom as Cottenball. I did a fresh install of version 4.105. When I run it for the first time, I am asked for a location for the database, I select the location and the window just starts to appear and then quits. Deleting the files that you suggested in the last threat did not change the behavior.

Here is the output of the debug file:
Microsoft Windows XP [Version 5.1.2600]
(C) Copyright 1985-2001 Microsoft Corp.

C:\Documents and Settings\HF>calibre-debug -c "from calibre.gui2.main import mai
n; main()"
Traceback (most recent call last):
File "C:\Program Files\calibre\library.zip\calibre\gui2\main.py", line 1192, i
n initialize_database
File "calibre\library\database.pyo", line 802, in __init__
File "calibre\library\database.pyo", line 565, in create_version1
OperationalError: unable to open database file
Traceback (most recent call last):
File "debug.py", line 96, in <module>
File "debug.py", line 80, in main
File "<string>", line 1, in <module>
File "C:\Program Files\calibre\library.zip\calibre\gui2\main.py", line 1294, i
n main
File "C:\Program Files\calibre\library.zip\calibre\gui2\main.py", line 219, in
__init__
File "calibre\library\database2.pyo", line 352, in __init__
File "calibre\library\database2.pyo", line 341, in connect
File "calibre\library\database2.pyo", line 384, in initialize_database
File "calibre\library\sqlite.pyo", line 107, in run
calibre.library.sqlite.DatabaseException: unable to open database file
RemoteTraceback (most recent call last):
File "calibre\library\sqlite.pyo", line 80, in run
OperationalError: unable to open database file

No log file was created but I have seen one on other tries. I deleted it and it did not reappear.

Kovidgoyal, thank you for your tireless efforts on behalf of the community. You helped me when I first joined.