Contact Support is an option on the Help menu.
To disable the Contact Support option, follow these steps.
On your Mac, select to open Spotlight.
Type "Terminal" > Return.
Type the following command, and then press Return:
Defaults write com.microsoft.Outlook DisableContactSupport -bool TRUE
Quit and restart Outlook (Outlook > Quit Outlook). When you select the Help menu, you'll see that the Contact Support option is gone.
To reinstate the Contact Support option, type this command, and then quit and restart Outlook:
Defaults write com.microsoft.Outlook DisableContactSupport -bool FALSE