.edu sites are Educational sites, hence the edu. .org sites are sites by organizations, which can be trusted, depending on the research that you do. That and Government sites are good sites to check as well as they are generally well trusted, that is unless the Government site is just covered by propaganda.
reassess and add better security to his wireless network
Based on the scenario being described within the question it can be said that Louis should reassess and add better security to his wireless network. This is because this unrecognized client is someone who has entered his home network without authorization. Most likely due to Louis not having the correct or any security on his wireless network.
The correct answer is that Dante did not click the Save and Close button before exiting the appointment.
When you make a change to an appointment in the Outlook calendar you need to click on Save in order to have the change saved in your calendar. If you do not do this the appointment will revert back to the original time and date when you exit the program.