Darktable is not opening: "Error locking database"

Question

After I installed the Inkscape (I believe that it was just after the installation of this software), my Darktable application is not working. The software just does not start and sometimes it shows the error:

darktable error locking database /home/tiago/.config/darktable/data.db
the database lock file contains a pid that seems to be alive in your system

I tried to delete the library but it always shows that the directory does not exist and/or nothing happens. I'm kind of new using Ubuntu command line and I don't know if I really deleted the file, but it still not working.

How can I fix this problem?

Answer 1

This happens to me sometimes, when Darktable does not shut down cleanly (for example if Ubuntu crashes). The way to resolve this is to remove the lock file(s) preventing Darktable from starting.

You can delete them, or if you are concerned about deleting just move them to your Desktop temporarily. Then delete them once you see Darktable working again. You should not lose any data or changes to your library.

The files to remove are ~/.config/darktable/data.db.lock and ~/.config/darktable/library.db.lock.

To access these files open Nautilus and press Ctrl + H to show hidden files, then navigate to the .config/darktable directory.

Alternatively you can open a Terminal window and execute mv ~/.config/darktable/*.db.lock ~/Desktop.

(Note that ~/ is the same as /home/tiago/, it's shorthand and easier for others to copy and re-use)

Answer 2

I had the same issue. I played with unetbootin and spoiled something.

I can't say that the advice does help 100%, but I realized that after this error message darktable starts anyway, just wait 5 - 10 sec.

I deleted the files, including data.db itself. It won't prevent the error on start, but then the program starts as usual in the second window.

Gurus, who can explain?

BTW the files situated at a different location in the newest program updates: ~/snap/darktable/54