Which OS do you use ?
If you are on linux and your standard locales is in dutch, C::B will show the dutch compiler-messages.
Use the envvar-plugin to set "LC_ALL" to "en_US[.UTF-8]" ("Settings.. -> Environment -> Environment variables").
Don't type the brackets, the should only show, that ".UTF-8" is optional (depending on your systems preferences.
If you are on windows, I don't know how to change it.