Sending email through Mailpro’s SMTP server takes about ten minutes from start to first message. The exact steps depend on the tool you’re configuring — CRM, e-commerce, monitoring system or your own code — but the four pieces of information are always the same: host, port, username, password. This guide walks you through the standard setup, the test phase and the most common pitfalls.

Before you start: You need an active Mailpro account with SMTP enabled (every paid plan includes it). Open the dashboard and confirm you can see Account → SMTP credentials.

Step 1 — Get your SMTP credentials

From the Mailpro dashboard open Account → SMTP credentials. You see four fields:

FieldValueNotes
Hostsmtp.mailpro.comSame for all accounts
Port587 (recommended), 465 or 2525Use 587 with STARTTLS
UsernameYour account emailSame as your Mailpro login
PasswordGenerate from this screenShown once — copy immediately

Step 2 — Configure your application

Most tools have a single “Outgoing SMTP” settings page. Paste the four values, set encryption to STARTTLS and authentication to LOGIN or PLAIN. Save.

Step 3 — Send a test message

Use the tool’s built-in test feature. Send to a real mailbox you control (preferably Gmail or Outlook to verify deliverability). The first test confirms the connection. The second test from your real workflow confirms the integration end-to-end.

Test outcomeMost likely causeFix
«Connection refused»Firewall blocks port 587Open outbound 587 or try port 2525
«Authentication failed»Wrong username or passwordRe-copy from the SMTP credentials page
«TLS handshake error»Encryption setting wrongUse STARTTLS, not SSL/TLS implicit
Test sent but never receivedSpam folder or DNSCheck spam, then verify SPF/DKIM

Step 4 — Add SPF, DKIM and DMARC for better deliverability

Sending will work without these records, but inbox placement will suffer. Add a Mailpro SPF include, generate a DKIM key in Account → Authentication and publish a DMARC record (start with p=none for monitoring). See our deliverability guide for the full setup.

Important: Sending from a generic address (gmail.com, yahoo.com) through Mailpro will fail or land in spam due to DMARC alignment. Always send from a domain you control.

Step 5 — Monitor and rotate

Open Reports → SMTP statistics regularly to spot bounces and complaints. Rotate your SMTP password whenever a developer leaves the team or you suspect a leak — the new password takes effect immediately.

Common SMTP code reference

CodeMeaningAction
250Message acceptedNothing to do
421Service unavailable, try laterImplement retry with backoff
450Mailbox temporarily unavailableSoft bounce — will retry automatically
554Message rejected (spam, DMARC, blacklist)Check sender reputation

Send through Mailpro SMTP in 10 minutes

Mailpro’s SMTP sending server works with WordPress, Magento, Salesforce, Odoo and any tool that speaks SMTP. Read the full SMTP setup FAQ.

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