Thunderbird not saving sent mail
Posted on Jul 12, 2010 by Paul White
If you find yourself in a situation where thunderbird is no longer saving your sent emails in the Sent folder, then I might have a solution. In my case all emails from July 4th 2010 on were not showing. That and anytime I clicked on my Sent folder it would take a very long time to load. If any of these symptoms sound like your problem, then my solution should work. Keep in mind by the time I got to this solution I had already gone through and deleted my .msf files, ran compact folders, and even created a new profile. None of these solved the problem. In short the problem was a bad email in my sent folder. The solution was to delete this bad email from the Sent folder then let thunderbird reindex it. Now doing this is not easy. You have to manually open you sent folder and find the bad email. For those of you who don't want the history of this problem, here is your quick and dirty solution
Solution: Thunderbird not saving sent mail
Open Thunderbird and take note of the most recent email in you sent folder ( this is your offending email )
Download the free 30 day trial of 010 Editor for Windows
Make of a copy of your Sent Data file from your Profile directory on thunderbird, and paste it to your desktop
Open your Sent Data file with 010 Editor
Find the starting and stopping address range of the offending email
Select this address range, and delete it.
Save your changes.
Recopy your Sent File back to your Profile Directory
Delete the Sent.msf
Open Thunderbird, and now all your sent mail is showing.
Causes of Thunderbird not saving sent mail
In my case I recently changed my mail server to handle up to 1 GB attachments. This was to make it easier to send emails to and from my clients ( who are also hosted on my mail server ). The problem was a 200 MB zip file I emailed my client. Of course Thunderbird tried to save this email with the attachment to my Sent Folder. Well I guess Thunderbird is not too keen on huge attachments. That and my Sent folder was already 4.3 GB in size.
I knew that this email was the cause because it was the last one that Thunderbird had record of being sent. so I figured that logically the large attachment was causing problems for Thunderbird. So I had to delete it directly from the Sent data file. Once I deleted it, I allowed Thunderbird to reindex the updated copy of my Sent data file, and all my emails could now be seen. Hope this helps someone else out. For reference I was using Thunderbird 3.1
This problem happened again recently. My theory was that maybe Thunderbird doesn't like large Folders. It just so happened that my sent mail folder was just a little over 4GB in size. Unlike Outlook which uses a single PST file to store everything. Thunderbird uses a individual file for each Folder. But if you are like me and use a Global Local Folders to store all your email, and you have a dozen or so email addresses, your sent Folder can easily get very large. Turns out after some research that Thunderbird does have a Limit of folder sizes, and that Limit is 4GB. The problem is once you go over this limit, your email still get saved, but you can't see them. This has to do with 4GB being the maximum addressed called by a 32bit software program. And yes Thunderbird is only officially available as a 32bit. There are some third party 64bit Builds of Thunderbird but I wouldn't trust them.
What to do if you go over 4GB for a folder size in thunderbird.
The problem is if you go over 4GB in size you won't be able to compact the folder, until you get the file size down to under 4GB. In my case I was trying to get the sent folder working again. so I listed out what I could see of my sent folder, and then sorted the messages by size. I then started to delete the large emails that were not anything I needed to hold on to. After doing this and deleting the sent.msf files from my profile directory. I still could not compact folders. So what I did was figure out the most recently email I could see in my sent folder. Then using 010 Editor I searched for that email. Then deleted the email after it. Then once again I deleted my sent.msf file,and opened up thunderbird. Now I could see all my sent mail. I ran compact folders and the filesize of my sent folder dropped to 2.2 GB, and everything is working again.
Hopefully in the near future they will release a 64bit version of thunderbird that won't have this 4GB cap on folder sizes. Even with this issue. I would still take thunderbird over Outlook any day.