Hi, please install a dictionary for spell check to work : https://addons.mozilla.org/en-US/firefox/language-tools/ Please let us know if this solved your issue or if need further assistance.

''CSBurks287 [[#question-1219057|said]]'' <blockquote> The box is checkmarked, but the spell check still doesn't work. I've tried installing and uninstalling the language (En-GB). I still can't get it to work. I check by intentionally mispelling stuff, but the spell checker never works. </blockquote> The Language Pack is only for the language of the User Interface or UI as the inline Spell Checker uses dictionaries. Only the en-US and maybe a couple other locales of Firefox from www.mozilla.org/firefox/all/ comes with a dictionary as the en-GB locale does not. https://addons.mozilla.org/firefox/language-tools/ On top of page there is a description <blockquote>Installing a dictionary add-on will add a new language option to your Firefox spell-checker, which checks your spelling when you fill out Web forms. Language pack add-ons change the language of the entire application.</blockquote> https://support.mozilla.org/en-US/kb/how-do-i-use-firefox-spell-checker https://support.mozilla.org/en-US/kb/use-firefox-interface-other-languages-language-pack Normally people would only install a language pack if they want to change the UI of Firefox between different languages. A single install of a locale can be downloaded from www.mozilla.org/firefox/all/

Thanks guys

Thanks guys. I wasn't aware I needed to download the dictionary, just the language. Finally got it to work.