---
title: "Email Not Sending: Troubleshooting Guide"
description: "Sending failures are commonly caused by authentication, password, port, quota or reputation problems. ## Check in Order 1. Test sending from webmail. 2. Confirm the mailbox password. 3. Verify the outgoing server and port. 4. Enable SMTP authentication. 5. Use…"
url: "https://vertico.co.zw/docs/email-not-sending-troubleshooting-guide/"
updated: "2026-07-23"
category: Troubleshooting
---

# Email Not Sending: Troubleshooting Guide

Sending failures are commonly caused by authentication, password, port, quota or reputation problems.

## Check in Order

1. Test sending from webmail.
2. Confirm the mailbox password.
3. Verify the outgoing server and port.
4. Enable SMTP authentication.
5. Use the full email address as username.
6. Check mailbox and account disk quotas.
7. Record the complete bounce or error message.
8. Check whether only one recipient or all recipients fail.

## Bulk Sending

 **Important:** A normal mailbox is not designed for unsolicited or high-volume marketing email.

## Need Help?

If you still need assistance, open a support ticket through your Vertico client account and include the affected domain or email address, a screenshot of the error, and the approximate time the problem occurred. Never send passwords by email or support ticket.