To fix the issue, you need to enable "My Outgoing server (SMTP) requires authentication" and Select "Use same settings as my incoming mail server"
Two way to do it:
Option 1:
- Open outlook (if closed)>> File >> Accounts settings >> Accounts Settings
- Double click on your email account
- Click on "More settings"
- On the outgoing server tab Tick the box "My Outgoing server (SMTP) requires authentication" and "Use the same settings as my incoming mail server".
Option 2:
- Close outlook (if opened) >> Click on the start button >> Type "Control Panel" and click on it
- Click on Mail (Microsoft Outlook)
- Click on "Emails Accounts"
- Double click on your email account
- Click on "More settings"
- On the outgoing server tab Tick the box "My Outgoing server (SMTP) requires authentication" and "Use the same settings as my incoming mail server".