I have a Macbook Pro 15" with Touch bar and Touch ID. The company has been bought from a Finnish store, and its language was Finland when bought. I changed it to English after booting up the computer first time.
Now there is an issue with OS language in some dialogs. Some OS dialogs show up in Finnish language, even when my only language in settings is English. Languages work correctly on my iMac and older MacBook Pro Retina.
For example, Thunderbird shows an OS dialog for entering password to secure storage, and its contents are in Finnish:
This is not limited to Thunderbird, but also other software show dialogs partly in Finnish language.
So, at first I just added English, chose it as a primary language and then deleted Finnish from Language & Region settings.
When I tried to fix the issue, I added Finnish again, set it as preferred language and then removed it again. There was no change to behaviour.
Then, I also tried the instructions described in https://discussions.apple.com/thread/7348459?start=0&tstart=0.
That is, I added and removed the Finnish language, tried reseting the PRAM and also ran sudo languagesetup, selecting Finnish as the language. None of these changed the behaviour.
I wasn't able to find any other suggestions in Google.
Any ideas what I can try?
Is there some cache for language stuff that is out-of-date?
Best Answer
After looking up into the issue more closely, I realised it was only ThunderBird initiated system dialogs that contained Finnish language.
I was able to fix this by downloading Thunderbird again, making sure to download the English version, and then installing it over current installation. This fixed the issues with language dialogs.