How to Fix the “550 Relaying Denied” SMTP Error

If your outgoing email bounces back with "550 Relaying Denied" (or "relay access denied"), the mail server is refusing to send a message on your behalf because it does not believe you are allowed to. In almost every case, the cause is simple: your email program is not logging in before it tries to send.

The good news — this is one of the most fixable email errors there is.

Why it happens

To stop spammers abusing servers, mail systems only relay outgoing mail for authenticated users. If your outgoing (SMTP) settings skip authentication, the server sees an anonymous request and blocks it. That block is the 550 error.

Step 1: Turn on SMTP authentication

In your mail app's account settings, find the Outgoing / SMTP server section and make sure it is set to authenticate:

Enable "My outgoing server (SMTP) requires authentication".
Choose "Use same settings as my incoming mail server".
Confirm the username is your full email address, not just the part before the @.

Step 2: Check ports and encryption

Use the recommended outgoing settings:

SMTP port 465 with SSL/TLS, or 587 with STARTTLS.
Incoming: IMAP 993 (SSL) — see recommended mail settings if you are unsure.

Step 3: Confirm the password

An outdated password can look like a relay error in some apps. If you have recently changed it, re-enter it — or reset it and try again. See updating your email account password.

Frequently asked questions

It works on my computer but not my phone. Why?

Each device has its own outgoing settings. The phone is likely missing SMTP authentication or using the wrong port. Apply the same fixes on the phone's mail account.

I get the error only when emailing outside addresses.

That is the classic sign of missing authentication — the server lets you send to local mailboxes but refuses to relay to external ones until you log in. Enable SMTP authentication and it clears up.

Still stuck after all this?

Some networks block mail ports. Try an alternate SMTP port (587 instead of 465), and if it persists, open a support ticket with the exact bounce text.