From Outlook to Thunderbird and Back Again
The process of exporting email from Outlook to Thunderbird on Windows is really easy. Exporting it from Thunderbird and importing in to Outlook is not hard either, just time consuming. Both ways can be done.
Outlook to Thunderbird
This is actually really easy. The first thing you need is all your email in Outlook. Then, when you setup Thunderbird it will ask you if you want to import your Outlook email. Say yes and it does all the work. No, Thunderbird doesn’t have an import function for the PST file, but it can import anything that’s in Outlook on the same machine. It’s as easy as that.
Thunderbird to Outlook
This process is a bit more complex . Outlook doesn’t directly import Thunderbirds email, however with the right tools, and some time, it can be done.
The first thing you’ll need is a program called IMAPSize. It’s a free Windows application that has a built in tool called mbox2eml. This handy program is used to convert Thunderbird’s mbox email files into eml files. The mbox files are found in your Thunderbirds profile folder (usually in the mail -> local folders). If you don’t see any files with the extension mbox, then it’s the ones without an extension.
The downside here is that each folder you have in Thunderbird is a seperate mbox file. You have to convert each one. Anything in a sub folder will have to be converted too and you may start to loose your folder structure. Oh well, you can always put it back together later.
Once everything is in eml format, you must now startup Outlook Express! That’s right, Express. No need to setup an email account in there, but you should setup all your folders to mirror what you had in Thunderbird. Then, open the folders on your computer that were created from the mbox2email tool and drag the individual eml files into the corresponding Outlook Express folders. You can drag and drop as many eml files as you want, but you can’t drag in a folder. Once you’ve copied all your emails into Outlook Express, you can now import them into Outlook.
Startup Outlook, create your profile and once that’s all setup, go to Import/Export, import from another application and choose Outlook Express. If I remember correctly, it first said it couldn’t import the email then it asked me if I wanted to import all the email. I said yes and all the folders and emails were imported into Outlook.
So there you have it. Importing email from Outlook to Thunderbird is pretty simple and importing email from Thunderbird to Outlook can be done. Depending on how many emails and folders you have will determine how much time it will take. Defiantly going from Outlook to Thunderbird is easier and quicker!
For a much more detailed process of moving from Thunderbird to Outlook, check out this great tutorial: Export Thunderbird to Outlook.












I installed Thunderbird for a client who was using Outlook Express as part of the install it asked do i want to bring over the Address Book, Messages and Settings, I indicated Yes. That took some time, but once completed the messages did not come over and now I cannot find Outlook Express (the program) anywhere on the hard drive and of course lost months of emails!!!
- jdb March 12th, 2008 at 9:29 am
Mozilla Firefox 2.0.0.12 - Windows XP
I highly doubt Thunderbird would delete Outlook Express. Something sounds fishy there.
- Thomas March 13th, 2008 at 8:13 pm
Safari 523.15 - Mac OS X
[...] From Outlook to Thunderbird and Back Again. [...]
- My Worklog » Blog Archive » Converting FROM Thunderbird to Outlook… March 19th, 2008 at 1:03 am
WordPress 2.3.3
Your description of transferring Outlook to Thunderbird is great - if they happen to be on the same computer. I’m looking for a way to move email from my work laptop to Thunderbird on my home desktop. Any ideas for that? Thanks.
- Bruce Southworth March 26th, 2008 at 8:39 am
Mozilla Firefox 2.0.0.12 - Windows XP
Hi Bruce. What email client is your work laptop? If Outlook, can you install Thunderbird on the same machine for conversion purposes? Then move the files home?
- Thomas March 28th, 2008 at 5:28 am
Safari 525.13 - Mac OS X
Not a bad idea - it may be do-able for the short term purpose. Our security conscious IT department frowns on any extraneous software being loaded on corporate computers. Thanks.
- Bruce March 29th, 2008 at 1:38 pm
Mozilla Firefox 2.0.0.13 - Windows XP
Or do you have Outlook at home?
- Thomas March 30th, 2008 at 9:02 pm
Safari 525.13 - Mac OS X
Outlook to Thunderbird
I used you suggestion and it appeared to work fine.
Most of the messages were well converted.
However, some of the messages are now displayed in html.
What happened?
- Fernando May 5th, 2008 at 10:39 am
Mozilla Firefox 2.0.0.14 - Windows XP
Am looking at installing thunderbird on corporate computers and import outlook express 5 on macos.
if I import emails from express 5 to TB do I lose any emails from the express 5?
Whats the pros and cons?
- gpo May 6th, 2008 at 5:51 am
Mozilla Firefox 2.0.0.14 - Windows XP
GPO, I don’t see any reason why you’d loose emails. Just make backups before syncing to be sure.
Fernando, I’m unsure about your issue. I’m not well experienced with Outlook.
- Thomas May 8th, 2008 at 5:52 am
Safari 525.18 - Mac OS X