How to Use Thunderbird 2.0 with UW CSE IMAP

Thunderbird 2.0 is a cross-platform, open source email client from the Mozilla organization with roots in the late venerable Netscape Communicator and Mozilla application suite. It includes an integrated threaded newsreader and RSS/Atom client. This document describes how to set up the email component to work with UW CSE IMAP servers.

(A "community-supported" internet application suite from Mozilla called "Seamonkey" also contains an email component. Wsers who prefer an application suite over standalone web browsers and email clients may choose to use Seamonkey. Configuring the email component of Seamonkey is quite similar to that of Thunderbird, and we expect this document to be useful to Seamonkey users. Notable differences are explained.)

1. If necessary, install Thunderbird. General-purpose lab-supported Linux machines have Thunderbird pre-installed.

2. If you are using Seamonkey, open the browser. To start the email client, click on the envelope icon near the bottom lefthand corner. Or select "Mail & Newsgroups" from the "Windows" menu. Or use the key combination Ctrl-2. (Thunderbird users: start Thunderbird directly.)

3. If you don't already have an email account configured in Tunderbird— as we assume here— the New Account Wizard will appear. You are creating a new email account. Click "Next."

4. Thunderbird next needs to know your name and email address. Enter that (your own, not mine, please) information, and press "Next."

5. Now, we tell Thunderbird that we want to use an IMAP account (choosing POP3 here will also work, but that's not what we are doing in this HowTo, and IMAP is a better choice for most users). The best mail server names to use are <username>.mail.cs.washington.edu. My username is rose, so I entered rose.mail.cs.washington.edu. Press "Next" again.

6. Yes, you have to tell it your username again. At our site, your username is in your email address, but that's not true at some sites (such as my %$@# ISP). "Next."

7. Thunderbird also wants a name for the email account. I used my email address (which is the default behavior) for that, but it could be anything— this name is just for your use in distinguishing the account from others you may have. "Next."

8. Message to the contrary notwithstanding, congratulations are not really yet due. Review the settings and click "Finish" anyway. You are looking at an email client screen that looks a lot like this (on Seamonkey, like this).

Note: you can't successfully connect to the IMAP server until you complete the next few steps, but Thunderbird will try (and fail) as soon as you finish the New Account Wizard. Just cancel that operation.

9. Now we need to reset some of the default settings to make Thunderbird work at CSE. Get to this screen by selecting "Tools" (Seamonkey or Thunderbird on Linux: "Edit") from the menu bar and "Account settings" (Seamonkey: "Mail and newsgroup account settings") from the submenu (or by right-clicking on the name of the account that you entered in step 7 and selecting "Properties." The account name will be in the lefthand pane of the mailer window).

10. Click on "Server Settings" to get to this screen, then click "Use secure connection: SSL." This is what keeps your password from leaking onto the network.

Other settings on this screen are a matter of personal preference. For example, some people like to see their email as soon as it arrives and set the interval for checking down to just a few minutes. Others like to check for email with an explicit action. You decide.

11. Click "Advanced" (even if you think you aren't). Our IMAP servers do not support folders that contain both messages and subfolders. That's not the default setting, so uncheck that box and click the "Okay" button.

(If you enter mail as the IMAP server directory in this dialog box, all of your folders will live in the mail subdirectory of your Unix home directory. An advantage is that the text-based Pine email client expects this, so you will be able to share your email with Pine f you find yourself needing to use a text-based client. Works with Outlook, too.)

(The "IDLE" command is indeed supported by our IMAP servers. If you check the corresponding box, you will see an indication of incoming email as soon as it arrives at the server. That way, you can start ignoring it even sooner!)

12. If you are an Exchange user, you are used to being able to type the names of local users into the To field of messages and having the fullname and email address autocomplete. That capability is based upon the standards-based directory service that Microsoft calls Active Directory, but our Unix-base email infrastructure has a service based upon the same standards. It's called "LDAP." We are now going to configure the mailer to use it. It's optional, but worthy.

(Also notworthy on this screen is the "Compose messages in HTML format," which is checked by default— what else would you expect from a web browser shop? Uncheck this box if you wish to compose messages in text format by default.)

13. To get to this screen, click on "Use a different LDAP server," then click on "Edit Directories."

Actually, the "Name" can be anything you like, but there is no room for creativity in the "Hostname" and "Base DN" fields. You can ignore the rest of the fields.

Note: if you are configuring a mailer on a non-.cs.washington.edu host, you must check the "use a secure connection (SSL)" box and the "bind DN" field needs to be set to the same value as the "base DN" except:

For me, then, the value of "bind DN" would be

uid=rose,ou=Account,ou=Computer Science &
Engineering,o=University of Washington,c=US

After entering those changes, make sure "UW CSE" is the selected directory server.

15. We have to fix up the "Outgoing Server (SMTP)" section, too. Check the "User name and password" box. Under "Use secure connection: TLS." Set the "Port" field to 587 (N.B.: as of June 2005, the former default port number value of 25 is deprecated and in fact will not work with many servers, notably smtp.washington.edu).

16. We are in the home stretch. Let's check our mail by pressing the "Get msgs" button near the top lefthand side of the main mail client window. We are starting a conversation with your IMAP server.

You will have noticed that we are using "SSL" for incoming and its sibling "TLS" for outgoing email. SSL is based upon the use of a "server certificate," a chunk of data that Thunderbird expects to be digitally signed by a "certificate authority." Getting them commercially signed costs money, and we've got a lot of them, so the University signs them for us. Standard builds of Thunderbird haven't been configured to recognize the University's certificate authority as a valid one, so the first time you go to check your mail, a warning window like that at right may appear. If so, click on "Accept this certificate permanently" and then click "Okay"; if not, you are using the UW CSE build of Thunderbird, which has been preconfigured to recognize the UW Computing and Communications CA.

If you are configuring a non-CSE build of Thunderbird, you can avoid the warning dialog and the need to blindly accept the indentity of the service by following the instructions in Adding a Certificate Authority to Thunderbird.

17. The IMAP server wants you to prove your identity, which requires you to provide your kerberos password (the same one you use to authenticate to the CSE web and to log into Unix machines). Any email waiting for you will now be downloaded to your Inbox.

18. You may choose to check the "Use Password Manager to remember this password" box, in which case you will not need to enter your kerberos password each time you check your email or send outgoing email. If you do so you will be presented with the warning dialog below, which recommends that you establish a "master password." Such a master password is requested by Thunderbird the first time in each session that it is asked to provide your password to the mail service (and every now and again for other security-related operations). The master password is used to encrypt the password store on disk; without it, your kerberos password (and others you may use with other email accounts) could conceivably be stolen by a malevolent user that gained access to your machine.

To establish a master password, select "Options" from the "Tools" menu, then select "Privacy" and click on the "Passwords" tab. Check the "Use a master password to encrypt stored passwords" box, then click the "Set Master Password" button to establish a master password.

19. Now, let's send a message by clicking on the "Compose" button near the top lefthand side of the main email client window. The screenshow shows how things look when we default to sending mail in text format; the screen for HTML email is a little busier. Yes, there is support for sending (and receiving) attachments. Click on "Address" for fine-grained control over who gets the message. Click on "Send" when you are ready to send.

20. You will probably wish to create some folders for storing your email. You do that by clicking on "File" on the menu bar, then "New:Folder." As you will recall from step 11, our IMAP servers don't support both messages and subfolders in the same folder. In this example, I am creating a folder called "applause and accolades" that will contain (only) other folders.

Note: all of this was performed using Thunderbird 1.5.0.7 on Windows XP, but there are very few differences between platforms, and not that many differences between recent versions of Thunderbird.

In short, in the /mailspool/folders/<username>/ directory on the host serving your Unix home directory.

Thunderbird also creates

Local
Folders

— mail that you drag into

Local
Folders

is local to the machine where the client is running, while the mail in your <username>@cs.washington.edu folders are available on any computer and any IMAP email client that you configure to access it. That's the beauty of IMAP: you can access the same repository of email from multiple locations and with multiple clients.

The IMAP server keeps track of which files and directories are used to store mail. Those are your "subscribed" folders.

The list of subscribed folders is known to the server, and the client queries for it at startup. That means that you can use one client to create or delete a folder, and other clients will learn about it without the user having to take explicit action. For example, you might create a folder from your work machine, then later use your home machine to check your email. The new folder will be known to the home machine. With our IMAP servers, the folder list is implemented using a file called ~/.mailboxlist. Don't delete that file!

Thunderbird provides a means to subscribe to a folder. That's useful for cases where you have a file in Unix mailbox format that you created outside the IMAP service— for example, if you had email from another service that you were migrating to CSE IMAP. In this case, you can use Thunderbird to browse the file system and identify those email folders that contain email you wish to subscribe to. Thunderbird tells the IMAP service about those folders, which are then available to any IMAP client you use with your email.

Some people prefer to use the UW SMTP service at smtp.washington.edu (instead of <username>.mail.cs.washington.edu). To use that server, you need to authenticate with your UWNetID credentials.

You can use an arbitrary number of email and newsgroup accounts with Thunderbird. Email accounts can use either the IMAP or POP protocols. Follow these steps to create a new IMAP account:

Thunderbird has built-in help. Click on "Help" on the menu bar (in Seamonkkey, then select the "Using Mail" section of the help). Besides the configuration topics covered in this document, they explain how to actually use the mailer. The sections on "Controlling Junk Mail," "Importing Mail Messages," "Working Offline," and "Signing and Encrypting Messages" are all interesting.

I configured my account to compose messages in [HTML,plain text], but sometimes I want to send a message in [plain text,HTML] instead. Must I edit the account settings just to change the mode for one message?

If you press and hold the Shift key when pressing the "compose" button, you will override the default for that one message.

Yes, with some effort you can, using the External Editor add-on for Thunderbird. Read about it here.

Yes. More precisely, you can migrate your email to be used with any supported IMAP client. Imagine that you wish to migrate an MH folder called CSE666 to IMAP. First, create the folder CSE666 as a folder for messages. (I am assuming that, like me, you are keeping all your folders in a subfolder called mail.) Then, at a Unix prompt, execute the following command:

packf is actually an MH command that converts the one-file-per-message MH format to, by default, the Unix "mbox" format that our IMAP servers can use.

Thunderbird Help has a section on importing mail and mail settings, and promises help (that I haven't reviewed) for users of Outlook, Outlook Express, and Eudora.

Name:	UW CSE
Hostname:	directory.cs.washington.edu
Base DN:	ou=People,ou=Computer Science & Engineering,o=University of Washington,c=US

How to Use Thunderbird 2.0 with UW CSE IMAP

Frequently Asked Questions