Outlook 2003 - Thunderbird Smack Down

Cedric Beust, April 23rd 2003

I have never been able to settle for a long time on One True Email Client.  Over the years, I typically switch back and forth between whatever the free client du jour is (used to be emacs + VM, then emacs + gnus, then Mozilla mail, then Thunderbird, then...) and Microsoft's clients (Outlook Express, a long time ago, and more recently, Outlook 98, Outlook XP and Outlook 2003).

I wish I didn't have to do that but the fact is:  email is very important for me and I am very unforgiving if my email client stops delivering the goods for my daily needs.  A couple of years ago, I left Outlook because its IMAP support was very poor and kept locking up the interface.  I switched to Mozilla Mail and then to Thunderbird.

After using Thunderbird for six months and being relatively happy with it, its little quirks eventually got to me (more on this below) and I switched back to Outlook.  Well, Outlook 2003 this time.

It's been a month now and I have kept a precise record of my various findings.  Below is a list of pros (+) and cons (-) for both tools.  I'll give my personal impression at the bottom of this article, but hopefully, you will be able to tell for yourself which tool is best for you.


+ Bayesian filter.

I have to commend Thunderbird for its Bayesian filter.  It didn't take a lot of training before reaching a cruising speed that was quite satisfying.  I have no doubt that it's gotten even better now.

+ Colored citations.

This is a trick I found on the Thunderbird Web site (sorry, I am too lazy to find the link).  Basically, it's a little bit of CSS wizardry that allows you have levels of citation colored differently.  For example, three levels will be dark grey, two levels will be little lighter, etc...  You no longer need to count the number of ">" or vertical blue bar to know exactly who said what and which parts of the text you are really interested in.  I haven't found a way to do this in Outlook yet, although it's certainly possible.

+ Paste as quotation

I do this all the time:  copy some text in the clipboard and then paste it in an email to comment on it.  "Pasting as quotation" is a real timesaver for me and I miss it a lot in Outlook (I usually resort to coloring the pasted text in a different color).

+ Good behavior in responding

Thunderbird is usually pretty smart to de-indent the text when you start typing your response.  It also has a more Netiquette-friendly way of responding to emails (at the bottom) although responding at the top of the email is sometimes quite desirable as well.

+ Usenet

I read newsgroups less and less these days but it's good to have my email client act as a Usenet reader as well.  Outlook doesn't do that by default but there are a few plug-ins such as Newsgator that will fill that gap.

- Flaky IMAP support

It looks like Outlook is not the only one found wanting in this area, although at least Thunderbird uses threading more efficiently and pretty much never locks up while retrieving IMAP folders.  However, things get really strange when folders are created behind its back.  Or deleted.  I eventually found myself in the situation where Thunderbird would refuse to remove an IMAP folder from its tree even though it was no longer present in the IMAP server.  Worse:  every attempt of selecting it ended in an error dialog box telling me exactly that ("this folder doesn't exist any more").  Well, how about offering to remove it from the tree?!?

- No integration with calendar

This didn't used to be a big ticket item for me, but it sure is now.  I have been using the Outlook calendar for a while now and I really want my email and calendaring to be more integrated.

- Missing important rules

I found Thunderbird support for rules less powerful than Outlook's (or procmail, for that matter...).  It's very primitive and it is missing some very crucial ones, such as "Stop processing more rules" (very important) and "Display new email window" (more of luxury, but I got used to it).

- LDAP doesn't work

Maybe I missed something, but I was never able to tell Thunderbird to use our corporate LDAP server to complete email addresses inside the company.

Outlook 2003

+ Mark for Follow-up

A feature I haven't seen anywhere, yet it is so important.  When an email arrives and I don't have time to respond right away, I can mark it "for follow-up" and also set a reminder in my calendar ("Respond by Tuesday 10am").  Before having this feature, I used to keep such emails in my Inbox and make a mental note of it, but this approach obviously doesn't scale.  Also, marking for follow-up means setting a flag on the said email, which can be of several colors.  I have grown quite fond of having my Inbox containing emails colored in various ways, it gives me a good sense of the work I have to do and allow me to do some quick pre-sorting in a visual way.

+ Search folders

This is a very neat feature.  Outlook lets you create "search folders" where you basically specify which folders are being searched and with what criteria, therefore giving you a selective view of your various folders (similar to a projection in SQL).  The emails in these folders are just links, so there is no duplication of information.  Let me stress again that these search folders can cover an arbitrary number of folders, such as Deleted Items, Sent, etc...  A good example of using this feature is to have a Search Folder for emails marked for follow-ups, so you can see what emails are pending a response from you at a glance.

+ Shortcuts

This is such an incredible GUI idea I am surprised I have never seen it before.  It is not Outlook specific but yet so convenient.  Outlook shows you a "Favorites" pane on top of your regular hierarchy of folders where you can drag and drop your favorite folders.  Tree widgets are being used everywhere these days and as a consequence, they can become quite big (mine is enormous since I am using Outlook as an RSS reader on top of that).  Having a Shortcut window with a dozen of important folders right in my face is invaluable.

+ Resend

Open Source email clients are usually better than Microsoft ones when it comes to Netiquette-related matters, but this is a blatant counter-example.  When an email bounces and you want to resend it, Outlook makes this very easy and also allows you to change the From address.  Doing the same thing in Thunderbird is quite a pain and involves a lot of drag and dropping and copy/pasting.

+ Fast completion

I like the way Outlook completes on email addresses and group aliases much better than Thunderbird.  It's blindingly fast and works very well with an LDAP server.

+ Integration with calendar

This feature is already useful in itself, but it really shines in the presence of an Exchange server.  With this, I can right-click on the sender of an email and know right away when she would be available for a meeting.

+ Spam programs

Outlook's default Junk filter is very poor (it doesn't do Bayesian filtering, only email blocking or whitelisting) but there is a free add-in call SpamBayes (written in Python) that works quite well.  It's not as fast as Thunderbird's spam filter, though, but there are also a few commercial programs that probably perform even better.

+ Powerful rules

The number of criteria and actions that Outlook 2003 offers is nothing short of staggering.  Whatever you want to do, you can probably do it.

+ Block images

While you could rightfully say that previous incarnations of Outlook (XP and under) were vulnerable to viruses, this no longer applies to Outlook 2003 which actually offers some features that no other client offers.  Blocking attachments is par for the course these days, so I'm glad it's finally done automatically, but Outlook 2003 will also block images in emails by default (which you can turn off for specific senders by adding them to your address book).  Once in a while, I still happen to open spam emails and I am tired of registering in their Web site stats as my client is trying to fetch their monstrous (or extremely tiny) images.

+ Three-pane display

Outlook 2003 introduces a new (optional) display where folders, list of emails and content of the selected emails are stacked up vertically.  It's quite disruptive at first until you realize it's the best use of real estate.  A lot of studies have been made on the subject and it's a well-known fact that past a certain width, reading text in a wide window becomes slower.  The sweet spot is probably somewhere between eighty and a hundred columns, and the three-pane display is a pretty good illustration of that.  The downside is that email subjects sometimes get chopped off but it's usually not a big deal since you can hover your pointer on the message to get some additional information, in case the first words of the subject didn't give you a good idea of what that email is about.  Then again, kudos to Microsoft for innovating.  They will no doubt be copied on that very soon.

- Thread display

Displaying threads in the Outlook pane has improved a lot, including a staggered view of messages representing the various follow-ups, but it's still not as pleasant as Thunderbird.  I won't expand on that, it's probably a subjective thing.

- Rules are flaky

This is undoubtedly my biggest gripe with Outlook 2003:  sometimes, rules just stop working altogether.  It has something to do with client-side versus server-side (if you're using Exchange) rules, but even with that in mind, I wasn't able to come up with a good interpretation of Outlook 2003's erratic behavior.  What I learned is that if at some point, one of your rules doesn't get called, it's probably because a rule above it is busted and interrupting the whole flow of execution.  Move your rules up and down until you identify the culprit, then delete it and recreate it.  I have about twenty rules right now and they all work satisfyingly, but it took me a while to get there and I find this kind of bug absolutely unacceptable (and I didn't find any help on the Web, and only a few people who had a similar problem, so maybe it's my environment).

- Rules can't be plugged in

Outlook is more than a program, it's a whole platform, and numerous add-ins happily reuse its various COM and .Net interfaces for results that are quite good (such as Newsgator).  However, it doesn't seem possible to add new rules or actions, which is a surprising oversight since spam add-ins need to resort to hacks to plug inside Outlook.  Hopefully this will happen in a later version.


Well, that took longer than I expected.  It should be pretty clear to you by now that Outlook 2003 has my preference these days, and Microsoft has packed their software with a lot of features that are going to be hard to beat, both in the "private organization" and "corporate environment" spaces.

Note that I tried to keep to a minimum the number of advantages for Outlook 2003 when tied to an Exchange server, since it wouldn't be fair to Thunderbird which doesn't have a counterpart.  But even as a standalone email client, Outlook 2003 is a very impressive piece of software.  Let's hope Thunderbird will rev up and rise to the challenge.

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