There are two possible solutions you can try:
1. Make sure Outlook/Outlook Express are properly allowed through your Firewall. Configure your firewall software to grant full access to the Internet for the following executable files.
For Outlook Express: Msimn.exe
For Outlook: Outlook.exe
2. If you have the Norton Antivirus or Norton Internet Security enabled on your device, you may have to do additional configuration to use Outlook or Outlook Express. In most cases, the Norton Anti-Spam feature is known to cause this type of connection issue. To test, you can try disabling the feature by following these steps: https://support.norton.com/sp/en/us/home/current/solutions/v1083859