Sometimes, the files Duik needs to run smoothly get corrupted, especially (but not only) on macOS or when something like OneDrive or DropBox is messing with your documents folder. If this is the case, Duik may not even be able to start anymore, or may be showing a script alert at start. In this case, follow the procedure described in the Troubleshooting section to repair Duik.

Generally speaking, the first thing to do if you have an issue with Duik is to follow this procedure.