Helping people with computers... one answer at a time.

My guess is that your email provider has some kind of a size limit that is preventing large emails from being sent.

I've received various emails that have pictures, etc. and when I click on "Forward" and I just add my email contacts and nothing else, these refuse to be sent and just stay in my outbox. Additionally, I get the error message, "An unknown error has occurred."

In this excerpt from Answercast #59, I look at a situation where emails appear to be to be too big to forward.

Stuck emails

Unfortunately, it's difficult to say exactly what's happening here. But, my guess is that your email provider, the service that you are using to send your email (which I can see here is Gmail) has some kind of a size limit that is preventing large emails from being sent.

Now normally, your email service provider will give you a more descriptive error message, usually something to do with the email being literally too big.

Time out

However, there are scenarios where the size of the email means that it takes so long to upload to your email provider when you send it, that the email provider actually thinks it takes too long - and times out.

What that means is even before the email service provider understands just how big this thing is, it gives up on trying to receive it all. It simply takes too long.

So, I really don't have a good answer for you - maybe another email provider or a faster internet connection might be one way to go.

Internet based solution

Since you're forwarding, the only real thing I can think of (if it's worth the effort for you) is to take the attachments, to take the contents of that email, and put them on to some kind of a file sharing service. Or use something like Dropbox where you can place them on the internet, and then simply use a link to those items rather than including them in the email.

So unfortunately, I don't have a direct "This is what you need to fix" solution. But I think I kind of understand exactly what's going on here. The email simply is too big.

Either the email service provider is telling you it's too big or it's so big that it's taking too long to get uploaded.

Article C5888 - October 5, 2012 « »

Leo Leo A. Notenboom has been playing with computers since he was required to take a programming class in 1976. An 18 year career as a programmer at Microsoft soon followed. After "retiring" in 2001, Leo started Ask Leo! in 2003 as a place for answers to common computer and technical questions. More about Leo.

Not what you needed?

Peter Lawrence
October 9, 2012 8:56 AM

When I send something out to various addresses, just occasionally one of those recipients rejects the email (my sister's often rejects messages) and I get a 'non-deliverable' mail from my ISP saying they were unable to deliver; you know the sort of thing, we've all had them. But when it does that, the email gets stuck in the 'Outbox' but Outlook keeps trying to send it but not just to the un-deliverable address, to everyone on the original list. Hence they all get mutple copies but the original email is still stuck in the Outbox until I delete it.

bob D.
October 9, 2012 11:35 AM

email stuck in outbox??,,,,, 1) (no i am not a share owner of yahoo) why would anyone in their right mind use windows for email send receive etc ????? 2) for free you can get yahoo email address, with inbox, etc, but no need for outbox because when you click "send" it is sent and immediately you get a page that says "was sent", etc,,,,, 3) no, dont bother getting email address with hotmail, they suck wind all the time, and dont bother with email add at google because you need at least 2 doctorate degrees in "disneyland tripping" to answer the commands and never do get the address unless you are lucky and favored by the gods..... 4) yahoo has all that the other freebies have plus better customer relations folks helping you with any and all probs you have, their pages on finance etc are excellant even tho some of their writers are cavemen...... 5) on other hand, of all others keep google in mind for when 'ask Leo' can not solve (never gonna happen) your problem google can plus they have an on site usgovt snoop surfing all traffic on net and scooping out any adverse to usgovt 6) also note that you can have a zillion yahoo email addresses, so can do fancy modern accounting via separate address for primary functions such as business, personal stuff, and whatever you save in big quanitity because of your own personal interest,,,, no limit folks, and, yahoo has the machinery so no problem no matter how many email add they issue, good folks to deal with, esp now they have CEO Meyer, yes a gal, but one with empathy thus you gonna see big changes and big things happen with yahoo ongoing, no kidding here ....

bob D.
October 9, 2012 11:43 AM

also: Leo notes above that slow or dead outbox delivery by windows etc are because your email is too long esp if you include the attachments,,,,, whereas Yahoo has no limit that i know, on yahoo i send email with more than 10 pages of 12 pt (normal size so the usgovt snoops dont get blind and brain dead) type and never bother with attachments which i put in the body of the email and send all in one shot nice and neat and easier on my reader to comprehend and use.... if i had a problem sending e.g. 100 page of 12pt type email, i would highlight and click 8 pt, which is not readable, most of my readers would know to highlight and click 12 pt to get back to normal, for those who dont then they cant read anyway so no loss, etc....... point is when Leo was upgrading windows os, gates made his mark and lots of loot off Leo and his skills, but now that he is no longer with microsoft/gates (naw gates could not function well without Leo so he quit the business and is busy globe trotting saving mankind esp cavemen), we gotta suffer with the anique w-os which means we still using w-95 no matter if gates is calling it w-8 or mickey mouse or whatever, the os is same and still tops ....

Peter B
October 9, 2012 12:58 PM

Since you appear to be using Gmail, then providing that the e-mails are still on their server (so you are using IMAP), you can just log on to their online interface, and send the e-mail from their online inbox. (Or you can sign up for Yahoo and do the same - as suggested above).

I have also had a similar problem to yours - in my case the e-mail came into an old e-mail address, and when I forwarded it (using the 'default' old address) I no longer had access to the outgoing mail server. In this case changing the e-mail address I was sending from to my current e-mail address sorted out the problem.

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