You'll need the full path if you want to create desktop shortcuts using a switch, such as to open Outlook to a specific folder (use the correct path to your version of Outlook.exe): If you use Vista or Windows 7, you can type the command line in the Start Search field on the Start menu, or on the Start screen in Windows 8 and Start menu in Windows 10. Paths that include spaces between words must be enclosed in quotation marks (') and are case sensitive.
Before using a command line switch, you need to close Outlook and verify it's closed in Task Manager's Processes tab.