This quick troubleshooting guide will help you checking the language configuration with screenshots and basic questions.
Module used here is Writer. Once it's fine with it, do the same for the other modules and change the Paragraph styles to Cell, Slide, ... styles.
For further details, see the [Tutorial] Spell check and Language configuration
.1. Check the dictionary extension is installedGo to menu Tools>Extension Manager
Check that the extension corresponding to the language you want appears:
NB: if you see a "multi-user" icon, it just means that the extension is installed for all the users of the computer (English dictionary above), else, it means that the extension is in the user profile and is available for the current user only (French dictionary above).Do you see the dictionary extension with your language?Yes
⇨ Continue to next postNo
⇨ Go to that section of the tutorial: 4. There is no dictionary for my language