Zettelkasten according to Luhmann, a tool written by Daniel Lüdecke

The Zettelkasten, in English one could say, hm, slip box (?), is a tool which supports organizing notes according to the principles Niklas Luhmann used for his ideas. It was programmed by Daniel Lüdecke in Java.

There are a few minor bugs which can be worked around easily, but one problem is considered highly dangerous from those who experience it: The program named ZKN3 says that it is about to load data and the user should wait… But to no avail! The program hangs and never comes back to life.

Today, 2019-05-20, we know that there are two possible solutions to the problem:

  1. Create an empty file with the extension .zkn3, double-click it or choose zettelkasten.exe to open it with. In the now hopefully running application use File/Open to load your precious data file.
  2. The other way is, to rename or even delete the pertinent file by the extension .zks3. This file contains startup settings, and if it gets corrupt it hinders ZKN3 from starting. If there is no .zks3 with the correct name, ZKN3 creates a default new one.

As a measure of safety you may from time to time export (!) your most valuable files as .zkx3 files! If you later on manage to start ZKN3 with an empty file, you must only create an empty note in this empty .zkn3 file. Afterwards you can import (!) the aforementioned .zkx3 file and everything’s fine again. If you don’t create the meaningless first note, you can’t import and get a warning message instead.

Please, help the community by posting your experiences with this error here:


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