This article applies to PRTG Network Monitor 12 or later

Enabling Multibyte Characters for PRTG Graphs

If you want your graphs to display multi byte characters that are not part of your character set (e.g. in sensor names), they will be displayed as little boxes at the top of your graph images.

To fix this, you can modify PRTG's language file.

Steps to Go

WARNING: The procedures described in this article are intended for advanced users only! Please keep a proper backup of all your entire setup!

1. Open the PRTG program directory and navigate to the language sub folder.
2. In this folder, identify the language file of the language you're currently using with your PRTG installation (e.g. English.lng).
3. Copy this file and rename it (e.g. English_mod.lng). Leave the copy in the language folder and make sure you keep the file extension .lng
4. Open that copy in a (unicode enabled!) text editor and find the <chartfont> and <chartfontbold> entries. Change the font name values so they specify a font that is able to display the desired characters. In the following, please find an example for the display of Japanese characters in an otherwise English context: <chartfont> meiryo.ttc </chartfont> <chartfontbold> meiryob.ttc </chartfontbold>
   Note: We recommend using Arial Unicode MS (arialuni.ttf). You might need to obtain and copy this font to the PRTG server first, as it is not part of standard Windows installations. Usually, MS Office installations will include it.
5. Save your work.
6. Now, please open the PRTG Server Administrator program from the Windows start menu. For the Select System Language setting, select your newly edited copy from the drop down list. Close the Server Administrator by clicking the Ok button and confirm restart of the PRTG service.

Done

That's it! PRTG will now use the new font for graph rendering. If you still see little boxes instead of multibyte characters, please delete the PRTG graph cache.