Home Forums Event Espresso Premium message not allowed – headers not compliant [291]

message not allowed – headers not compliant [291]

Posted: February 12, 2021 at 7:48 am

Gary Ray

February 12, 2021 at 7:48 am

I am receiving the following error in response to confirmation emails that the system sends out. I do not receive this error for all recipients. The error is “message not allowed – headers not compliant [291].” I am using a custom template for the confirmation email but do not believe that I changed the headers at all. Please advise.

Gary Ray


  • Support Staff

February 15, 2021 at 1:47 pm


It’s possible for another plugin to modify the email headers. This is because Event Espresso uses the WordPress wpmail function, which has filter hooks to allow for filtering the email headers. So the first thing to check is if there are any other plugins activated on the site that also send out mail. They may be running code on the filter hooks to change those headers.

As an aside, the error message seems to indicate the recipient uses a email address.

The support post ‘message not allowed – headers not compliant [291]’ is closed to new replies.

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Status: closed

Updated by  Josh 2 weeks, 2 days ago ago

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