Magento 2.1.1 language switch doesn't work.

[MirkoHufnagel]

Dear Community
 
We have Magento 2.1.1 installed, together with the "Porto" template and a second (german) language pack.

Language in the backend works fine.

 
Unfortunately, it works not with the language change in the store. On the home page, I can still change the language from english to german. Now my german main menu is visible. So far so good.
If I select something from the german menu it jumps directly to a 404 - why? Because the language from the store jumps back to english and the URL .../german-category/germanarticle,html doens't exist for english.
 
Thank you so much for any helpful information.
 
Best regards

Mirko

[oceansoftvn · Accepted solution]

You need to install it with the official guide of magento with the command.

Please visit http://devdocs.magento.com/guides/v2.1/config-guide/cli/config-cli-subcommands-i18n.html#config-cli-... for more details