You can do this in the applications's preferences dialog. Select the "Language" category and change the language. Depending on how you installed the application, the language files may not be on your computer, and you will have to re-run the installer and e.g. install the German translation.
If "German" does not show up in the list on the language selection dialog, select to be prompted for the language the next time you start the application. I've seen that work better than picking the language in the dialog.
Karl Heinz Kremer
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