Where is the system locale en_US.utf8?

I have probably deleted at the very beginning by mistake the file en_US.utf8, when I stupidly thought I wanted the store only in German. But where does the file belong and where do I get it from?

en_US.utf8 is a system locale. If you are running your own Ubuntu server see this link:
https://askubuntu.com/questions/89976/how-do-i-change-the-default-locale-in-ubuntu-server

I dont believe there is a Ubuntu server.

But for several things I wanted to do, I get an error message like this:
Warning: Failed setting locale en_US.utf8,en_US.UTF-8,english for en in ~/includes/library/lib_language.inc.php (Line 112)

But get not the result I wanted to achieve, respectively the message just tells me nothing.

The error message states there is no such system locale named en_US.utf8, en_US.UTF-8, or english in your web server.

If you are not the server manager then ask your server manager to install the english system locale. If you are the server mangager, turn to the right commands for your Linux distribution how to install locales correctly.

To list your available locales on a Linux server, run this Terminal command.
locale -a

Now we are severly off the topic of this thread. Please consider a new topic when going off topic in the forums. I have split the forum thread to a new topic.