How can I change the user-name in the folder-display ?

(The following terms are translated from German, but perhaps not correctly) At present I try to familiarize with W8 with a new Toshiba Laptop. There exists only one user with the name Helmut. I created a local account with the name „Helmut“. But in the folder-display *Computer --> xxx(C: ) --> users *appear only the two folders „Public“ and „TOSHIBA“. I tried with execute --> control...