“Load langs.xml failed!” is a really annoying error from Notepad++ that means syntax highlighting is broken.
langs.xml is a file Notepad++ uses to define the syntax of supported languages. Copies of the file live in more than one place.
Sean Walther’s instructions to fix the “Load langs.xml failed!” message have saved me once. In short, delete langs.xml from the Notepad++ application folder and replace it with a copy of langs.model.xml from the same folder before restarting Notepad++.
Today I had to try a different fix. Start a new cmd session and run the following command:
This deletes a copy of langs.xml from your profile’s Notepad++ configuration.
When you restart Notepad++, it should recreate a valid langs.xml in your profile, and syntax highlighting should work again.