Umlauts can be substituted with the following characters: ä - ae, ö - oe, ü - ue. The Esstset, or Scharf S, "ß", can be substituted with a double s; "ss". If your computer has Windows: go to the program "Character Map" in the folder "Accessories", find the characters and copy them into your text, or you can install the language on your keyboard via "Regional and Language Options" on the Control Panel.