This does not disable the No End Date option in Outlook, so users can still select it users can also change the end by date if desired. When Outlook is restarted, the end by date is the specified number of days from 'today' and selected by default. HKEY_CURRENT_USER\Software\Microsoft\Office\12.0\Outlook\Options\Calendar HKEY_CURRENT_USER\Software\Microsoft\Office\14.0\Outlook\Options\Calendar
HKEY_CURRENT_USER\Software\Microsoft\Office\15.0\Outlook\Options\Calendar Value data: number of days from 'today', after which the recurrence will end. HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Outlook\Options\Calendar In Outlook (all versions), add the following registry value to set an end date as default selection (replace xx with your version of Outlook): If you want to prevent users from creating recurring appointments with no end date, you can disable the No End Date option, also using the registry.
