After upgrading to Windows 10 you are unable to send email from Outlook.

You are still able to receive email but any sent emails get stuck in your outbox. Your sending settings are correct:

Cause

This is a known bug in the Windows 10 update process.

Fix

Following the steps in the Microsoft community fix below will help fix this issue and let you send email again from Outlook.

Steps to fix Outlook sending issue in Windows 10

  1. Press the Windows and X keys at the same time. A window with a list of options will open.
  2. Scroll down and click Command Prompt (Admin). The Administrator Command Prompt Window will open.
  3. Type sfc /Scannow and press Enter.
  4. Windows will now scan your system files on your PC and try to fix any errors.
  5. Once the scan is finished you may be prompted to reboot your PC.