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Sorry to hear you’re facing problems 
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Some or all of the below information will be requested if it isn’t supplied; for fastest response please provide as much as you can 
Nextcloud version (eg, 20.0.5): 22.2.6.2
Operating system and version (eg, Ubuntu 20.04): Ubuntu 20.04
Apache or nginx version (eg, Apache 2.4.25): apache 2.4.41
PHP version (eg, 7.4): 7.4
The issue you are facing:
Setting locale to en_US.UTF-8/fr_FR.UTF-8/es_ES.UTF-8/de_DE.UTF-8/ru_RU.UTF-8/pt_BR.UTF-8/it_IT.UTF-8/ja_JP.UTF-8/zh_CN.UTF-8 failed
Please install one of these locales on your system and restart your webserver.
Below the output for the locale setting.
# localectl
System Locale: LANG=en_US.UTF-8
LANGUAGE=en_US:en
VC Keymap: n/a
X11 Layout: us
X11 Model: pc105
in the config.php file I also use
'force_language'='en'
'force_locale'='en_US'
(I use ’ instead of " as seen on the language & locale section of installation. does it matter? all the other entries of the array have ')
Is this the first time you’ve seen this error? (Y/N):N
Steps to replicate it:
- I have no idea. I think after system auto update
The output of your Nextcloud log in Admin > Logging:
I can’t log in and I don’t know how to reach the admin log
I also used dpkg-reinstall locales and also rebooted apache and the server several time but nothing has changed.
Few days ago I updated NC with the CLI hopeing it will fix the issue but didn’t
Any hint on how to fix or where to look for the issue is welcome
cheers