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Why Does Mail to Me Bounce with “mailbox full” Only if it’s Over 1 Megabyte?

Question: I cannot receive any emails larger than 1MB but am able to receive emails less than 1MB. The email delivery statement reads that my mail box is full and cannot receive any emails. I just got done deleting all of my old emails. So my inbox should be almost empty. Could you please help me and let me know what I can d in order to fix this problem.

Without knowing exactly what email service and/or program you use, it’s hard to be specific, but I do have some ideas.

You might not have deleted what you think you deleted.

In fact, you might not have deleted anything at all.

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First, realize that if you’re running a desktop email program like Outlook, Outlook Express or others, the bounce message – and the out of space condition – almost certainly had nothing to do with that program or the disk space on your computer. Unless you went out of your way to configure it – if it even can be configured in the program you use – desktop email programs don’t send bounce messages.

What that means is that if you deleted email in your desktop email program, and you cleared up disk space on your PC, that actually had no impact on the problem.

Bounce messages and disk space restrictions come from your email service provider where your messages are stored until you either access them via a web interface, or download them using a desktop email program. Typically, that’s your ISP, but also includes web mail services like Hotmail, Yahoo, GMail and others.

And often there are limits on how much can be stored.

One problem that can occasionally occur with desktop email programs has to do with whether downloading works the most common way. Normally, we think of downloading email into a desktop email program as moving the mail from the server to your machine. That would imply that downloading frees up service space. But if you’ve configured your email program to “leave messages on server” – even for only some period of time – then the messages aren’t immediately deleted, and the space they take up is not freed. You’ll need to change that configuration option. (Be sure to understand why you have it set that way first – there might be a reason.) Alternately, you might use the email service’s web mail interface, if it has one, to truly delete selected emails.

When it comes to most online web-based email services most have incredibly large space allowances, but it’s still possible to fill ’em up. It’s quite possible that you have indeed exceeded the amount of space allotted to you.

One common issue is that when you “delete” mail in many email programs or services, the messages are in fact not deleted immediately, but rather moved to a recycle bin (not your desktop recycle bin, but a recycle bin or deleted messages folder that should be visible in your email interface). That may not actually free up the space. You’ll want to see if that’s the case, and explicitly empty the recycle bin to permanently remove the messages and free up the space.

There’s one final possibility: your email service has a 1 megabyte message size limit, and this is the error they’re reporting when they return a message that exceeds that limit. 1 megabyte seems very small, and the error message would seem incredibly misleading, but … it’s possible. Check with your email service for any possible size restrictions on incoming messages.

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2 comments on “Why Does Mail to Me Bounce with “mailbox full” Only if it’s Over 1 Megabyte?”

  1. If the user has a domain with several mail boxes, it is possible that one of the *other* accounts hasn’t been emptied and the ISP has a limit for the entire domain rather than the individual account. If that were the case for this user, the cure is to close the unused account or clear it of all back-logged mail and forward all new mail to a watched account.

  2. As an Outlook user, I also received a “mailbox full” message this month, and discovered that the problem lay with my webmail folders. When travelling, I would often check my ISP’s webmail facility for urgent items, but avoid replying or deleting messages until I return home. In time, my ISP blew the whistle on the size of my webmail in-basket, withourt explaining what was the problem.


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