550 5.7.0: message classified as spam or virus
The Telekom spam filter classified your message as spam or as carrying a virus and rejected it after the DATA phase. False positives can be reported.
- Telekom
- Provider
- Permanent (5xx)
- Class
- Sources checked
- Author
At a glance
- Code
- 550 5.7.0
- Provider
- Telekom (t-online.de)
- Temporary or permanent
- PermanentRefused for good: the message comes back to the sender, and resending it gets the same answer.
- Who has to act
- The sender. The fix is on the sending side: your domain, your server or your list.
- What the server says
550 5.7.0 Message considered as spam or virus, rejected
What it means
Telekom filters mail as it arrives and refuses what it judges to be spam or malware at the end of the DATA phase, so the message is not delivered. The reply is multi-line: it lists your IP, the receiving host, a timestamp, an Expurgate-ID and an authenticator code, in English and in German. If you see this often, Telekom asks you to stop your server from continuing to deliver the mail it classed as spam, and to resume only when the problem is solved. For a message you believe was misjudged, report the error codes to the address in the reply, FPR@RX.T-ONLINE.DE.
Common causes
- The content or links of the message look like spam to the filter.
- An attachment carries a virus or other malware.
- Spam leaving your server alongside normal mail.
How to fix it
- 01Stop the delivery of messages that keep being rejected this way.
- 02Check the message for content and links that may read as spam, and scan attachments for malware.
- 03For a false positive, send the error codes from the reply to FPR@RX.T-ONLINE.DE, or use the Telekom online form and forward the message with all its headers.
Sources
What this page rests on, checked on 20 Oct 2026. The explanation is ours; the reply text is the server's.
- t-online.de Postmaster (Deutsche Telekom)postmaster.t-online.de
Related codes
- 554IP address blocked.Telekom is not accepting mail from your IP address at all, usually after unusual mail volume from it. The reply names the contact to ask for review.
- 550Mailbox unavailable.The receiving server permanently refused the message for this recipient: the mailbox does not exist, cannot be reached, or the server rejected the message by policy.
- 5.7.0Security or policy refusal, unspecified.The message or session was refused for a security or policy reason that the server did not describe more precisely, or chose not to reveal.
5.7.0 at other providers
- 550 5.7.0Relay denied: sender not registered.Google's SMTP relay refused your mail because it comes from an IP or domain that is not registered in your Google Workspace account's relay settings.
- 550 5.7.0Relay account suspended for abuse.Google has temporarily suspended the account behind your relayed mail from sending, because it detected abuse such as spam from it.
- 550 5.7.0Email sending denied.Google refused to send this mail through its servers for your account, and its reply refers you to the SMTP relay error documentation.
- 552 5.7.0Blocked for a potential security issue.Gmail blocked the message because something in it, typically an attachment, looks like a security risk under its content and attachment rules.
- 503 5.7.0No identity changes permitted.Your client tried to authenticate again in an SMTP session where Gmail had already accepted a sign-in.
- 554 5.7.0Too many unauthenticated commands.Gmail closed the session because your client sent too many commands without signing in, on a service that needs authentication.
Further reading
All 3 Telekom codesEvery code in the wikiPaste your own bounce