Solution to Emails Delivered but Stuck in Outbox

The solution is very simple: empty the folder Sent Items.

It is a long story of getting to the solution. If interested, please read on.

In my office a dedicated artwork processing workstation receives and sends tons of emails everyday. The email program installed is Outlook Express. Artwork attachments are normally high resolution PDFs, JPEGs, etc. Every a few days my colleague asks me to examine this workstation when the symptom comes – emails stay in Outbox after sending, and an error message will popup saying one or more tasks are not completed but not giving details and possible reasons. Actually emails have been delivered many times before my colleague notes the problem.

The Outbox symptom occurs quite randomly. Sometimes even a small email without attachments could incur the problem, but big emails with attachments are more likely to replicate the problem. My previous approaches were focused on rebuilding a new Outbox. I have tried at least the following methods, none of them always work.The effectiveness is random as well.

  • Compact all the folds in Outlook Express
  • Export and import emails
  • Delete Outbox.dbx (Outlook Express will automatically create a new one when it detect Outbox.dbx does not exist)
  • Create new Windows user and import emails
  • Reinstall Outlook Express and import emails

But all of the above methods could only work for a while. I researched many IT forums. Lots of gurus mention that they face the similar problem and use the above temporary methods. So I had been used to being called for help once in a while.

Today I was called again. While trying my old methods one by one to see if any of these temporarily solve Outbox Symptom, I suddenly had some afflatus. Why I thought Outbox was wrong? I always used “outlook express outbox stuck”, “outlook express outbox stuck” as search terms. It could be Sent Items. My deduction is –

When Sent Items.dbx is getting bigger and bigger, some bugs in Outlook Express make Outlook Express not able to handle reliably a new Sent Item appending to Sent Items.dbx. That is why the Outbox Symptom happens randomly. The email is already sent but because it can not go to Sent Items, it has to stay in Outbox.

Sent Items.dbx on artwork workstation is 3 gigabyte huge. I renamed Sent Items.dbx to Old Sent Items.dbx and deleted Sent Items.bak. Instantly Outbox Symptom was gone. Now I know it is not appropriate to be called as Outbox Symptom. It is Sent Items Symptom. I believe my new solution will be permanent.

Looking backwards, even 3 articles (E-mail does not leave the Outbox, How to troubleshoot mail stuck in the Outbox in Outlook 2000, Error message that Sent Items remain in Outbox) I found from Microsoft knowledge base regarding this Outbox Symptom or Sent Items Symptom whatever did not help much. I do not expect my solution would be collected by Microsoft knowledge base, but I do expect this post can be ranked on top in google “outbox stuck” related search result, helping as many people as possible solving a very simple problem.


  1. Reading others asking for help about Outlook Outbox Symptom, I think Outlook has the similar problem. Although I did not have any chances to replicate the problem in Outlook and test my solution, I suppose my solution can be applied to Outlook as well.

  2. I deleted 800 mess. from my sent box and it worked like a charm. I guess sent box can only hold so many. since this is my work computer i keep all work related mess. I had over 6000. Is their any way to increase the capacity the sent box? I will try changing the file name tomorrow. I just can’t loose my e-mails.

  3. I think it is the size, not the number of messages, that make outlook express stuck. But I might be wrong.

    There must be a bug inside. I can’t do anything to increase the capacity. Sorry!

  4. Brilliant indeed! Cheers! If however I need something from the Old Sent Items.dbx how do I do? Can I use a new identity with another storing folder in which to set the “old sent” as current?

  5. Thanks.

    To access “old sent”, you needn’t create a new identity. The simplest way is create a folder under “local folder” or “sent items” or anywhere else. Because each folder has a separate dbx file, creating another folder and moving emails to that folder will keep sent items.dbx small.

  6. I know good tool,which works with Outlook Express files and possible Outlook files,it has many features,also it is free-rebuild outlook express,software can resolve data corruption issues for Outlook Express email client,works with one of the most vulnerable elements of information systems,helps and it does not matter, what happened with your mailbox,works with Outlook Express versions 5, 5.5, 6 and all currently supported versions of Microsoft Windows operating system,preview all messages, that can be successfully retrieved from corrupted files with dbx extension,recovery of all emails from your mailbox in dbx format, if these dbx files are seriously corrupted and Outlook Express there was an error opening this message,will save separate files of eml format, that can be accessed by any email program.

  7. I renamed Sent Items.dbx to Old Sent Items.dbx, however I don’t know how to copy contents of Old Sent Items.dbx into a folder I created under local folder in Outlook Express. Can you give me detailed instructions as to how to do that? Thank you.

  8. You can move emails in two ways –

    Easy way but take long if there are lots of emails in Sent Items:
    1. In Outlook Express, create new folder
    2. Drag and drop to move emails

    Quick way:
    1. In Outlook Express, create new folder
    2. Close Outlook Express, delete “new folder.dbx”, rename “Sent Items.dbx” to “new folder.dbx”

  9. Hi,
    Read through this while searching for a solution to my problem of:

    I have a stuck email in my outbox but Express won’t show me the email to delete it. I know I typed the email address wrong but Express keeps trying to send it there…

    I found that closing Express, going into :
    C:\Documents and Settings\Owner\Local Settings\Application Data\Identities\\Microsoft\Outlook Express\ and renaming Outbox.dbx to _Outbox.dbx then re-opening Express and sending a test email to get Express to recreate a new Outbox.dbx, which worked a treat :)

    Thanks for the thread. Andy

  10. My fellow on Facebook shared this link and I’m not dissapointed at all that I came here.

  11. This worked for me! I had a guy bring a machine in for the 2nd time with this problem! Finally a great answer. Thanks!

  12. I must have done something wrong. I saved my Sent Items.dbx to OldSent.dbx and deleted Sent Items.bak. I can see the OldSent.dbx when I explore all dbx files under Identity. I can’t seem to get it to show up in Outlook Express itself. Any suggestions?

  13. Very helpful, thanks for posting, it came up as the top result for me and it worked immediately!

  14. Brilliant!!

    I don’t understand how something so simple is not listed in any of the MS knowledge bases. This was driving me crazy. All of my emails were being sent but they were remaining in the Outbox and not moving to the Sent Box.

    I went in and deleted about 100mb of messages with attachments that had been collecting and it now works perfectly.


  15. 感激你無私的分享

    Our secretary come across this problem and she think the email cannot be delivered, so she tried to resend the email many times. Finally, she received lots of complaints from our clients about the duplicated emails. She felt very uncomfortable was unable to fall asleep at nights. Luckily, reading your article, resolves the tricky problem and she laugh again………… Thanks a lot for your sharing!

  16. Thank you so much! I did not even think about checking the sent items and it was HUGE. I renamed it to archive it and let her start fresh. Thanks!

  17. I have done all the things listed above.

    However I have one problem. Normally the sent items show who the mails are sent to. However when I create a new folder to store the old emails from Sent Items, the emails are all shown in my email address rather than the person or people they were sent to.

  18. A huge thank you – deleting heaps of old sent files , many of which included pictures, solved the problem. Thank you for posting the solution. Very much appreciated.

  19. Your solution worked! Thanks. I had tried the instructions from a different site, unchecking and checking boxes they specified and restarting the computer as they directed, but the problem remained until I followed your instructions. Thanks again!

  20. Dear 芳草苑主

    You gave a fantastic piece of advice. So many thanks as the actions you suggested seem to have worked for my OE issue.


  21. A client called me about an Outlook issue unrelated to Outbox. However, I noticed 300 items stuck there. Your article was the first one presented from a Google search.

    Your article worked!

Leave a comment

Your email address will not be published. Required fields are marked *