To use Howard's code, while in the VBA editor, if not already done, you might
need to select Tools -> References and check the box (Ensure you check the
box; don't just hightlight the line) against Microsoft Visual Basic for
Applications Extensibility 5.3.
In addition to above need to provide access to the VBA project. Select a
worksheet then:-
xl2007:-
Microsoft button -> Excel options -> Trust Center -> Trust Center settings
-> Macro Settings -> check the box against Trust access to the VBA project
object model.
Earlier versions of xl:-
Tools -> Options -> Security tab -> Macro Security button -> Trusted sources
tab -> Check the box against Trust access to visual basic project.