For OmniWeb 4.0.x (Mac):

  • Open OmniWeb's Preferences (under the OmniWeb menu).
  • Select the 'General' icon (if the icon is not visible, select 'Show All' first).
  • In the 'Start page' text field, enter "http://www.mercantil.com/".
  • Close the Preferences window to save your preferences.