Set Developer Options : Ribbon « Introduction « Microsoft Office Excel 2007 Tutorial

1. Microsoft Office Excel 2007 Tutorial
2. Introduction
3. Ribbon

Click the Office button, and then click Excel Options.

In the left pane, click Popular. 
           Select the Show Developer tab in the Ribbon.

In the left pane, click Advanced. 
           Select the Show add-in user interface errors.

Click OK.

1.2.Ribbon
	1.2.1.	The Ribbon replaces menus, toolbars, and most of the task panes found in Excel 2003
	1.2.2.	To minimize the Ribbon, double-click the name of the tab
	1.2.3.	Excel provides three types of tabs on the Ribbon
	1.2.4.	The Excel commands are organized in groups on the Ribbon, Office menu , Quick Access Toolbar, and Mini-Toolbar
	1.2.5.	Minimize the Ribbon
	1.2.6.	Set Developer Options