UNDO and REDO in Autodesk Inventor
You may want to undo an action that you just performed, or undo an undo. The Undo command backs up Autodesk Inventor one function at a time. If you undo too far, you can use the Redo command to move forward one step at a time. The Zoom, Rotate, and Pan commands do not affect the Undo and Redo command. To start the commands, select the command from the Quick Access Toolbar as shown in the following image. The Undo command is to the left, and the Redo command is to the right. The shortcut keys, using CTRL-Z for Undo and CTRL-Y for Redo.
To set the Undo file size allocation, click Tools tab > Application Options. On the General tab of the Options dialog box, change the Maximum size of Undo file (MB).