localhost doesn't find all files in Sites-Folder
Ok, i don't know why but i changed the Document-Root-Folder in the XAMPP-Config-File to match /username/Sites.

Now the other folders work, too. 

I don't understand why one folder works with the old configuration, and newer ones don't. 

To all with the same problem:


  The XAMP-Config-File must be the same document-root as the /etc/apache2 - config file on the mac


Strange thing, on my other Mac the Document-Paths are different but work.