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Why is my email bouncing because of too many being sent at once?


I’m operating a laptop with Windows 7, SP1 and Outlook 2010. I have three
accounts: (all of them use IMAP) BTInternet, Gmail, and I’ve been
getting sent messages returned marked as “Undeliverable due to the number of
emails being sent at once” despite documentation suggesting that there is no
limit to the number of addresses that can be added to a contact group.

Despite the fact that I’ve made one of the accounts as default, the default
account does not send the emails. Instead, one of the others sends it. How can
I make Gmail address the sender by default automatically?

In this excerpt from
Answercast #86
, I look at two problems in sending email: limits on the
number of emails that can be sent at one time and automatic reply-to


Too many emails sent at once

So there are two questions here.

One: I want to clarify who is imposing that limit on the number of emails being sent at once.

Contact groups in Outlook

A “contact group” is something that you can set up in Outlook itself.

Outlook can certainly maintain contact groups of any number of contacts. It will then allow you to send to all of those contacts at once by specifying the group as the recipient. That’s not the problem.

ISP limitations

The problem really has nothing to do with the use of contact groups. The problem is that the number of recipients on a single email is being limited by your email service provider. In other words, this is a limitation that’s being imposed either by BTInternet, by Gmail, or by – depending on which email account you’re sending it through.

So unfortunately, I don’t really know of an easy way around this.

I mean, if you were manually to type in too many email addresses, without using contact groups at all, you would get exactly the same error sending through that same email service provider.

The only way is to use a different email service provider. You’ve got three to choose from so I would try using one of the others – to see if perhaps they don’t have the same limit;

Or try sending multiple emails to a smaller subset of your recipients each time. I know that’s a bit of a hassle.

The problem is spam

The reason that the email service providers do this is because of spam.

The problem, of course, is that spammers want to send out thousands and thousands of emails as quickly as they can. One of the ways they do that is to send individual emails with a large number of recipients (usually bcc’d) all at once.

The email service providers have to crack down on that as one way to limit how much spam can be sent. So, if you want to blame somebody, blame the spammers.

Unfortunately, there’s really no clear work-around other than finding an ESP (an Email Service Provider) that has a higher limit – or breaking your message into several separate sends to a smaller number.

Set default email account

Now, your second question about “How do you make Gmail the sender by default?”

As long as you make sure that that’s the “default” account (which it sounds like you’ve already done), what should happen is that any new email you compose will, by default, go through that email account.

Reply-to defaults

The problem is when you reply to an existing email.

What Outlook normally does is it then uses the account that that message was received from to send it. In order to change that, you have to manually change your From address.

I believe in Outlook you can specify the “sending account.”

You may have to make a control visible on the Compose window to do that – so you may have to customize the Compose window a little bit to display the account selection drop down. You can send through one of your other accounts by selecting that other account in the drop down.

Basically, Outlook is trying to be helpful. What it’s trying to do is let you always respond on the same account on which an email was received. So if you receive it on Gmail, your response will go out through Gmail. If you receive it on BTInternet, then a reply would go to BTInternet.

You have to take manual steps to change that to one of the other accounts – if that is in fact what you want to do. In most cases, most people don’t. That Outlook behavior is pretty much exactly what most people expect.

So unfortunately, again, no simple answer there but hopefully somewhat helpful.

(Transcript lightly edited for readability.)

Next from Answercast 86 – How do I burn the latest Ubuntu to CD?

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2 comments on “Why is my email bouncing because of too many being sent at once?”

  1. Leo, I think your answer could have included a bit more detail.

    I have multiple email accounts related to my personal and my charity work. When I send an email, or reply to an email in Thunderbird, I can change the “sending account” but all that does is change the “From” line of the email.

    I have noticed that regardless of which account the mail is sent from, they all go through the same SMTP server. The reason, I found out is that in my Account Settings, I have only one SMTP server set up, so each email account in Thunderbird is set to use that server.

    I think the OP should check his settings to see if he has Google’s SMTP server set up and that it is set as the server to use.

  2. @James,
    The accounts will go through whatever SMTP server you have set for each account. You can set them for different SMTP servers only if your ISP allows you to do that. Again, it’s spam that’s the problem. Some ISPs block the ability to send through other servers, in that case, your only hope would be to send smaller batches of emails. Or even to buy one of the online services that send out newsletters and the like.


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