Try following these steps to change the device back to English:
1. Connect to the web configuration utility by entering the TeraStation's IP address in a web browser.
2. In the column of blue items on the left hand side, select the second link.
3. Under the first header are two text fields; enter or modify the text in the second.
4. Under the third header, the first entry is a radio selection with two options; select the one on the right.
5. Under the fourth header (with two menu/pulldown boxes beneath it),set both menu boxes to the second entry in the list (the second menubox should say cp437).
6. Click the button, and close and reopen the browser.