4.8.3. Error "450 4.7.1 Error: too many recipients from IP"

The error can be caused by attempting to send more than 300 messages per minute or messages with more than 300 simultaneous recipients (copies and hidden copies are also counted).

If you send more than 300 messages per minute, you need to configure mail sending so that this limit is not exceeded.

If an error occurs when trying to send a message with a large number of recipients, you should reduce the number of recipients to no more than 300 and try sending again. You can use WebMail.Online or WebMail classic to send individual messages to more than 300 simultaneous recipients.

The messages being sent already have less than 300 recipients, but the error still occurs. What could be the problem?

When trying to send a message with a large number of recipients through a mail client, situations may arise when after an attempt to send a message and an error occurs, the message is saved in the mail client in the sending queue (for example, in the "Outbox" folder) and the mail client periodically tries to send it again, which leads to a regular recurrence of the error. In this case you should find a mail client working from the IP mentioned in the error text, where this message is saved, and either remove it from the sending queue or reduce the number of recipients in it.

If there are many mail clients connecting to the mailboxes from the same IP and it is difficult to identify the desired mail client, you can change the mailbox password. This will break all active connections and disconnect all mail clients from the mailbox. ⚠️ After this operation you will need to manually specify a new password in all necessary mail clients.

Can the hosting staff tell me exactly which device is attempting to send from that is causing the error?

Unfortunately, no. Our server only records the external IP address of the sender. It is technically impossible for us to record by whom exactly attempts to send are made.

What to do if you urgently need to send a message, but now you don't have time to search for the mail client causing the error?

You can use WebMail.Online or WebMail classic.

Is it possible to individually increase the limits on sending frequency and number of recipients?

Alas, you can't, because the limits are not set for specific mailboxes or hosting accounts, but for the mail service as a whole.