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SMTP2GO ​

SMTP2GO

Reliable global SMTP relay with multi-region failover. 1,000 emails/month free; uses port 2525 to avoid ISP blocking.

Easy~5 minSMTP

Step-by-step ​

Sign up + verify your domain ​

smtp2go.com → sign up. SMTP2GO → Settings → Sender Domains → Add Domain. Add the DNS records (DKIM, SPF, return-path) shown.

Create SMTP credentials ​

SMTP2GO → Settings → SMTP Users → Add SMTP User. Pick a username and password (or let SMTP2GO generate one). Note both.

Add the connection in SendGrail ​

SendGrail → Connections → Add Connection → pick SMTP2GO.

Fill in: Connection Name, From Email (your verified domain), From Name, Username + Password from step 2. Save.

Port 2525

SMTP2GO uses port 2525 by default to bypass ISP blocking of standard SMTP ports. SendGrail pre-fills this.

Test ​

SendGrail → Test Email → pick SMTP2GO → send.

Troubleshooting ​

  • 535 Authentication failed — wrong SMTP user/pass. Re-check at SMTP2GO → Settings → SMTP Users.
  • Sender not allowed — From Email's domain isn't verified. Add DNS records and click Verify in SMTP2GO dashboard.
  • Connection timeout on port 2525 — your host blocks outbound port 2525. Try port 587 (also supported) or contact host support.

What's next ​

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