- Step 1: Go to your Windows computer and then launch the Control Panel window.
- Step 2: Click the System and Security link and choose the Windows Defender Firewall option.
- Step 3: Now, the Windows Defender Firewall window will display on the screen.
- Step 4: Click the ‘Turn Windows Defender Firewall on or off’ link on the left panel to aolve SMTP exception failure sending mail error.
- Step 5: Select the radio button next to the ‘Turn off Windows Firewall’ option.
- Step 6: Save the changes made in the Windows Defender Firewall window by clicking the OK button at the bottom.
- Step 7: This will disable the Firewall feature on the Windows computer.
- Step 8: Check if the SMTP exception failure sending mail problem has been resolved.
- Step 9: If not, try to change the port.
- Step 10: To get assistance from our technical experts in resolving the SMTP exception failure sending mail problem, click the Call button provided on this web page.