The officially supported languages for PRTG currently are English, German, French and Spanish. If you want to translate PRTG into other languages you can now download the PRTG Translation Tool and create your own translation. For each translation a so-called language file (.lng) must be created. This file contains about 5.000 strings which are used by PRTG to render the user interface. Our knowledgebase article How To Translate PRTG 7 Into Other Languages explains the process and has the download link, too. Ready to share your translation? Please join the prtg7addons project on the Google Code website and upload your language file. Just like our friend Gerard Feijth who has already uploaded his Dutch translation for PRTG.