I converted from Microsoft Outlook several years ago, and have not looked back since. Outlook is an excellent local email client with support for server synchronization, integration with the rest of the Office line of products and many mainstream legal document management systems. However, free and open source solutions such as Mozilla’s Thunderbird can offer the user many of the same features for a significantly lower price (free = $0 per license/seat/user). While many users would never divorce themselves from the concept of using Outlook, for small-medium size firms, solo practitioners, the newly formed law firm or if your Firm seeks to control licensing costs, Mozilla’s latest offering, Thunderbird 3.0, is one of the top alternatives on the market.
Email has become a vital and important part of law firm communication. It is used internally as a method for relaying case related information, the development of case strategy, the circulation of documents from within a document management system, sharing of research & case law and other various legal or administrative tasks. As many who also email regularly as part of their personal life, our Inbox is also a large part of our digital social lives, too. How users elect to manage all of this information is another thing – there are many choices on the market, but only a few truly “major players,” namely Outlook, Eudora, LotusNotes, SeaMonkey, and Outlook Express.
Thunderbird, a product of The Mozilla Corporation, the makers of the popular web browser Firefox, seeks to offer universal appeal, extensible options and many of the features that are popularized within Outlook. While it does not set out to be an Outlook replacement, it is by far the strongest open source / free competitor on the market today.

What can it do?
Basically, the vast majority of common email functions, and then some. Within Thunderbird you can connect to your corporate/POP3/IMAP or Exchange email account, Compose, Save as Draft, Send/Receive, Archive, Store, Print, Tag, Star for relevance or importance, create folders, manage a complete address book, utilize multiple accounts with separate folder structure within one “Smart Folder” interface and rely on specific security/encryption level settings.
What are the advanced features?
Compared to other email applications, Thunderbird has a bevvy of advanced features, many of which are geared toward content management. The archiving system, which is somewhat different than how Outlook handles it, enables the archival of past emails with easy retrieval. For law firms in particular, this can allow older case materials to be outside of your everyday work environment, but close enough should you need it. One of Thunderbird’s top advantages is extension management – the program has over 600 customized extensions, from PGP message encryption to popup/ad blockers. This means a user can customize what they want within their email client, and IT professionals can create a custom image or build that works with the variety of tools freely on the market.
The latest 3.0 version of the product has also clarified the scheduling of events and the management of inviting attendees. In prior versions, this was a complex task, however it has been greatly streamlined through an “Events and Tasks” menu option. In many respects, I believe Thunderbird does a better job at this than Outlook, especially in terms of event repetition, categorizing events and managing the privacy of attendees. Added support for various secure connection methods (SSL/TSL, session dependent), a strong search tool, retention policies and calendaring with the Lightning extension. Thunderbird’s offering has truly evolved since it’s roots. It can even detect whether or not you’ve referenced an attachment in an email and display a reminder if you haven’t attached anything yet. Thunderbird also supports Outlook’s PST container, so users can be transitioned with relative ease.
How does it compare to Outlook?
I’ve used Outlook for years, but find more features and extensibility in Thunderbird. While it is not easily embraced by many manufacturers of plug-ins or utilities that are often used by law firms, I have found a greater satisfaction using Thunderbird than almost any other email client. It’s latest iteration is not perfect, however for email management, scheduling, aesthetics and extendability one would be hard pressed to find a stronger alternative. The fact that it’s free helps, too. While I have never performed any brute force tests or valid experiments, I can report that Thunderbird has never crashed, frozen or locked on me in 6 years over several computers. Thunderbird can also be installed on an OS X or Linux computer, further adding to the value of the product. While many would be quick to point out that most firms exist in a Windows environment, the fact that it can also support OS X and Linux means you can offer a solution with however a user might choose to operate at home, on the road or in the future.
Is there integration for document or knowledge management systems?
Yes, but not all. While traditional providers such as Interwoven might not support a Thunderbird extension, O3Spaces does include integrating Thunderbird with a dedicated document management system. If you would like to test it out, they offer a free limited community edition and paid commercial solutions if you find that it meets your needs. For firms that might not implement a document management solution (which you should no matter your size), this could be a great way to beta test with a small group of users at a limited cost.
What should a Firm know before deploying or implementing it as a solution?
Thunderbird will require a limited amount of additional training for end users experienced in Outlook. The program is very straightforward in terms of it’s layout and menu structure, users will most likely not find issue with layout. Customization is a big part of the Thunderbird interface, so a Firm may wish to dedicate a portion of their training on creating a unique experience for each user. On the hardware side, Thunderbird is compliant with most server environments and will excel in a Linux/Zimbra environment. If you are already using a document management system or other series of plug-ins and consider using Thunderbird, discuss the transition with your providers before taking the leap. They may or may not be able to support it.
What’s the verdict?
Thunderbird is a capable product and can be an excellent choice for law firms that seek to transition from Outlook or are otherwise not using a dedicated email client (i.e. OWA or another web-based client such as Hotmail/Gmail). While it might not have the universality with niche industry plug-ins for document management, meta data or other KM solutions, a developer could be hired to further extend it’s abilities if these are important to a Firm already in love with the product. The software can also be installed on a machine with Outlook already on it. The download is free and can be tested while simultaneously using the software you (or your users) are already comfortable with.
Thunderbird might not have the backing and marketing of a billion dollar corporation, but the outlook (no pun intended) for this application within the legal community is excellent.
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#1 by Steven A. Schwaber on February 9, 2010 - 2:11 am
I am going to respectfully dissent from this glowing review. Let’s start by saying that I am a Mozilla fan and have used T’bird since version 0.8 and Firefox since 1.x. But this version of T’bird is a kluge (engineering slang for cobbing something together that barely works).
For starters, I had it on my machine (a low end XP-Home eMachines D2880) for less than a week and it crashed so many times I quit counting. I lay this onto the fact that it is a massive resource hog. After any of its numerous crashes, when it reloads it shuts down the video so that the program only partially covers the desktop/underlying window; to recover, I have to switch to any other program and then back to t’bird. Sometimes it takes so long to do anything (like open an email) that I go to task manager and see that it is consuming 98-99% of resources.
Then, let’s talk about the UI. Garbage, pure and simple. Tabbed browsing=good; tabbed email=No. At least when for 10 (or whatever) years, one has clicked on the upper right “x” box to close an email; using tbird (in between crashes, anyway), almost literally 95% of the time I ended up closing the program, not the email window. Any idiot who has read a Time magazine article or two on ergonomics would know that when you make a major paradigm shift in the UI, you include either an option to retain the old interface (even Bill Gates did this in allowing “classic views”), or you incorporate an option to not allow closing of the program with an open tab (hell, Firefox has had this for years, don’t those guys talk to each other?).
AFter a week, I found a website from which I could download v.2.0.0.23, and I am happily back with my old email client.
Beware this “upgrade”, at least on lower end systems. And if you are a creature of habit as far as the UI is concerned.
sas
#2 by Joseph Ficocello on February 10, 2010 - 3:05 pm
Thanks for your comment, Steve! I always appreciate every view on an issue. The stock specs on an eMachines D2880 says that it ships with 256 MB of RAM and a Celeron D processor. Unless you’d upgraded your RAM, Thunderbird 3 requires at least 1 GB of RAM on a Windows XP machine. They state this on their website. http://en-us.www.mozillamessaging.com/en-US/thunderbird/system-requirements/
This is most likely the cause of your issue running the application, as on that machine Windows alone would probably consume 30-40% of your resources. Coupling that with any other open programs, antivirus software and a few Firefox tabs, and Thunderbird won’t have much room to work. If you wanted to run version 3 on your existing hardware, you might want to consider dual booting into Linux as the kernel’s lighter than Windows. If you wanted to keep a version of Thunderbird on your D2880 with XP and limited RAM, you would definitely be better off using a v2 instance of Thunderbird. If you’d upgraded the RAM, have XP SP3 and still have the problem, I would probably say it could be the processor speed or maybe even a library conflict from the upgrade from v2.
Regarding the UI, most of their enhancements were a result of the user feedback they’d received from the millions who use the software. If you go to “View” on the toolbar and select “Layout” you can switch to classic view, and if you want to add/remove/move toolbar items you can go to View – Toolbars – Customize. Regarding the tabbed email, I actually like this because with a 3 button mouse you can tab open related conversations with a middle mouse button click, but you can turn this feature off http://support.mozillamessaging.com/en-US/kb/Message+Tabs
Please also note, all comments have to pass through our spam filter, checked for inappropriate content and be approved by an Administrator, so comments will appear as soon as we can add them. Thanks again!