Why was my message rejected?

When we send emails to non Gmail servers and recipients, these servers can sometimes refuse to accept Gmail’s attempts to deliver the message for numerous reasons. The error that the recipient server gives Google is included in our notification to you that the message was bounced/rejected by the recipient’s server.

In situations where the recipient is a Gmail user, we will include:

  • The rejection reason
  • Information link to learn more
  • “-gsmtp” at the end of the error

This distinction is important to determine if further investigation needs to be carried out by the recipient domain or by your Google Apps administrator.

Example rejection message by remote recipient domain:
Delivery to the following recipient failed permanently:

user@example.com

Technical details of permanent failure:
Google tried to deliver your message, but it was rejected by the server for the recipient domain example.com by mx1.example.com. [4.2.2.2].

The error that the other server returned was:
553 5.3.0 user@example.com... No such user

Example rejection message by Gmail
Delivery to the following recipient failed permanently:

unknownuser@example.com

Technical details of permanent failure:
Google tried to deliver your message, but it was rejected by the server for the recipient domain example.com by aspmx.l.google.com. [173.194.79.27].

The error that the other server returned was:
550-5.1.1 The email account that you tried to reach does not exist. Please try
550-5.1.1 double-checking the recipient's email address for typos or
550-5.1.1 unnecessary spaces. Learn more at
550 5.1.1 http://support.google.com/mail/bin/answer.py?answer=6596 uc1si15114930pbc.51 - gsmtp

Encountering '550-5.7.1 Our system has detected that this message is likely unsolicited mail'

Here at Gmail, we work very hard to fight spam. This includes not only spam coming into Gmail but spam being sent out from Gmail as well. Believe it or not, spammers sign up for Gmail addresses in large numbers just to send out spam! To help do our part to keep this junk off of the internet, we bounce mail that we are confident is spam. Unfortunately, we aren't perfect and will occasionally bounce legitimate mail. We apologize for the inconvenience.

There are a number of ways you can inadvertently confuse our automated spam filter, by sending suspicious-looking or spammy text, for example. By far the most common problem is sending mail cc/bcc'd to large numbers of recipients ("bulk mail") to send out newsletters, invitations, etc. Since spam is sent to many recipients, our spam filter is slightly more likely to confuse bulk mail with spam.

Depending on your needs, there are a number of different ways to reliably send bulk mail that avoid the pitfalls of doing it manually with Gmail. You may be interested in trying Google Groups for newsletters/mailing lists or Calendar for sending invitations to events. Also, many other Google sites like orkut, Picasa and Youtube offer the ability to automatically notify your friends when you update your profile or upload new pictures or videos, so you don't need to email them all yourself.

If you are a Google Apps user sending to a group, please see why a Message bounced due to Bulk Sender for additional information.

If you are sending mail in accordance with our guidelines and Gmail continues to mark your messages as spam, contact us.

Note: If you encounter this error when trying to report spam messages to third party authorities, we recommend using the following procedure instead:
  1. Click the down arrow next to Reply and select Show original on the message you would like to report.
  2. Using your browser's menu, save the page as a .txt file.
  3. In Gmail, click Compose to start a new message, address it to the appropriate agency, and attach the file you saved in step 2.