Configure MailWizz SMTP

The Problem

MailWizz is installed but campaigns fail, send painfully slowly, or get rate-limited, usually because the sending server connection is misconfigured or poorly matched to your sending volume.

About this problem

MailWizz being installed doesn't mean it's properly connected to a sending server — the SMTP or API connection has to be configured correctly, and sending limits need to roughly match what your chosen sending service actually allows, or you end up with failed sends, painfully slow delivery, or your sending account getting rate-limited or flagged.

This comes up most often right after installation, or when switching to a different sending service partway through using MailWizz.

What's Included

• Configuring the SMTP/API connection for your chosen sending server
• Setting sensible sending limits to match your provider's rules
• Testing deliverability with a real campaign send
• Troubleshooting any connection or authentication errors from the sending server

What's NOT Included

• Purchasing or recommending a specific third-party sending service
• Email authentication setup for the sending domain (separate service if needed)
• Fixing MailWizz installation issues unrelated to SMTP

How It Works

1. Configure the SMTP or API connection details for your chosen sending server within MailWizz.
2. Set sending limits (rate, concurrent connections) to match what your sending provider actually permits.
3. Send a real test campaign to confirm the connection works end to end.
4. Monitor for and troubleshoot any authentication or connection errors reported by the sending server.
5. Adjust configuration if sends are failing or being throttled unexpectedly.

In practice: you buy the service, send over whatever access or details the job needs, I investigate and do the work, and you confirm it's resolved before we call it done.

Frequently Asked Questions

Why are my MailWizz campaigns sending so slowly?

Usually because the configured sending rate doesn't match what your sending server actually allows — too conservative and it's unnecessarily slow, too aggressive and your provider starts throttling or blocking you.

What sending servers work with MailWizz?

Most standard SMTP servers and several major transactional email APIs are supported — the right choice depends on your sending volume and budget, though recommending a specific provider is outside this service's scope.

Why is my MailWizz SMTP connection failing?

Usually a mismatch in port, encryption setting (SSL/TLS/STARTTLS), or credentials between MailWizz's configuration and what the sending server actually expects.

Can I use multiple sending servers in MailWizz?

Yes, MailWizz supports configuring multiple sending servers and can rotate or load-balance between them, which is useful for higher-volume sending.

Does this service include setting up email authentication for the sending domain?

No — SPF/DKIM/DMARC for the sending domain is a related but separate service, since it concerns DNS rather than MailWizz's own configuration.

How do I know if my sending server connection is correctly configured?

By sending a real test campaign and confirming it delivers successfully without errors, rather than just saving the settings and assuming they're correct.