Displays the file tabs at the top of the drawing area.
Find
File tabs provide an easy way for you to access all the open drawings in the application. The file tab usually displays the full name of the file. Click the plus sign (+) on the right end of the file tabs bar to open the New Tab. 
Drag a drawing from Windows Explorer into any part of the file tab bar to open it.
Use Ctrl+TAB to navigate through the file tabs.
Note: Set NEWTABMODE to specify whether clicking the plus sign (+) on the file tab bar displays the New Tab or a new drawing.