to discard any changes to the workbook

 
     Private Sub Workbook_BeforeClose(Cancel As Boolean)
           ThisWorkbook.Saved = True
     End Sub

1.	If you want to prevent users from printing only particular sheets in your workbook, use this similar code instead:
2.	Preventing Users from Inserting More Worksheets
3.	If you want Excel to stop prompting you to save changes you didn't make
4.	Before Save event
5.	To link that tab's command bar to a right-click in any cell, enter the following code in the private module of ThisWorkbook:
6.	Pass value between events
7.	Workbook activation events
8.	minimizes the workbook's window:
9.	Workbook_BeforePrint
10.	use the BeforePrint event to add information to a header or footer before the sheet is printed
11.	BeforeClose event is used to delete a custom menu
12.	create your own Save dialog in the event:
13.	Set application key in Workbook Open event and BeforeCloseEvent
14.	Workbook open event
15.	Workbook Events Open: enable custom toolbar
16.	procedure is executed when the workbook is closed
17.	Workbook_SheetSelectionChange
18.	The BeforeClose event for a workbook
19.	The BeforeSave event for a workbook
20.	Activate and deactivate events in a workbook
21.	Cancel Close action based on the A1 value
22.	only allow the workbook to close if the figure in A1 is between 500 and 600:
23.	If you want to make sure that all changes are saved when the workbook closes

to discard any changes to the workbook : Workbook Event « Excel « VBA / Excel / Access / Word