This program supports the ability to undo and redo commands multiple times. Use the Undo/Redo options to control the amount of memory used to store command history, and/or the number of times the undo/redo information is stored for each active image.
To configure the Undo/Redo options:
Choose Tools > Options to open the Options dialog, and then click the Undo/Redo tab.
Mark the Limit undo/redo disk usage check box, and enter the number of megabytes that should be used to store undo/redo data for each open image in the Mbytes per open image field.
Mark the Limit number of undo/redo steps check box and enter the number of undo/redo steps allowed in the Steps per open image field.
Mark the Warn when operation cannot be undone check box if you want the program to display a warning message when an operation cannot be undone.
Click OK to close the Options dialog.
Configuring the Program Launch Bar