Howdy, Stranger!

It looks like you're new here. If you want to get involved, click one of these buttons!

In this Discussion

osTicket v1.10 (stable) and Maintenance Release v1.9.15 are now available! Go get it now

Mailer error. SMTP code: 450, response: 4.7.1 Error: too many recipients

Hi All,

here are the basic information,
osTicket Versionv1.10.1 (9ae093d) —  Up to date
Web Server SoftwareApache
MySQL Version5.7.14
PHP Version5.6.22
In the last month, I have received the following error repeatedly, 

 "Mailer Error

Unable to email via SMTP:<server>:25 [<our email address>] Failed to add recipient: <receiver's email address> [SMTP: Invalid response code received from server (code: 450, response: 4.7.1 Error: too many recipients from <IP address used also in the API of OSticket>)]"

The words between <> are used just to hide real email addresses and IPs. 

It happens almost daily, even though not every time that I send an email. Do you have any suggestion about how to troubleshoot it and what may be the cause?

Thank you in advance! (and let me know if you need more info)



  • So you said "The words between <> are used just to hide real email addresses and IPs. "

    How many recipients are we talking about?

    Your mail server is telling you that the email being sent has too many recipients.  That means your mail server is limiting the number to a certain amount and the email exceeds that amount.
  • edited November 2017
    Hi ntozier, thank you for your comment. I should have written that the recipients are actually only 1 or 2 in the worst case scenario.

    The traffic that OSTicket cause on the mail server is probably in the order of 20-25 emails per day (35 in a really bad day).
  • Then i dont know why your mail server would tell you that is too many recipients.
  • Thank you all the same ntozier. I will try to insist with the company that gives us the smtp service and see what they say. However, if anyone has any other suggestion, I am open.
Sign In or Register to comment.