There is a problem with transferring the Fischertagebuch user data to other computers or after a reinstallation of the operating system. After the transfer the Fischertagebuch will start with an error.
The problem will be solved in the next version of Fischertagebuch. In the meantime please backup the folder ".Fischertagebuch" (located in your user directory e.g C:\Users\Username\ Windows or /home/Username/ Linux) and restore it after the installation of Fischertagebuch on the new system.