Running from a USB drive
Beginning with version 0.7, Thunderbird can be run from a USB memory stick or other portable drive. In order to do this, you need to install Thunderbird (the application itself) on the USB drive, create a profile on the USB drive, and launch Thunderbird using the correct parameters so that it can find the profile on the USB drive.
It is important to chose a fast USB drive, because USB drives are slow compared to a hard disk. The USB 2.0 specification supports a theoretical peak transfer rate of 60MBs. However, in reality a generic drive might support only 2MBs reading or writing while a fast drive might support 30MBs read and 10MBs write. If the speed rating is listed as 150x, 200x etc. it is comparing it to the original rotational speed of a CD player. 1X is 150KBs .
This article was originally written for roving Thunderbird users, who take a USB drive from PC to PC. However, it can also be used by somebody who has installed Thunderbird on a hard disk and wants to run Thunderbird using a -profile "path" command line argument to specify the profiles location. This can be useful if you don't know whether your profile was corrupt or you had been running into problems with a bad profiles.ini file.
For Windows users, the easiest way to do all this is with Portable Thunderbird, which is an official build of Thunderbird that has been repackaged "as a complete, removable drive-friendly email client." One of its key features is a special launcher to make your Thunderbird extensions portable. To install, just download the ZIP file and unzip it anywhere on your USB drive.
You can upgrade Portable Thunderbird by installing a new version over the old one. This won't destroy any of your data (your profile) since its stored in a separate directory.
The most common mistake in using Portable Thunderbird is to run Portable Thunderbird, and then pin the Thunderbird icon to the taskbar. That typically pins Thunderbird.exe instead of the Portable Thunderbird launcher, and strange things such as installing a profile on your boot drive can happen. See Using a Portable App for how to avoid that.
There is only a Windows version of Portable Thunderbird . However, the application officially supports running it under Linux, Unix, BSD, etc via Wine and with OS X via CrossOver, Wineskin, WineBottler, or PlayOnMac.
-profile "path" command line argument
Even without Portable Thunderbird, it is fairly easy to run Thunderbird from a portable USB drive. The key is to launch Thunderbird using the -profile "path" command line argument, where "path" is the location of the profile you want to use. The path should be in quote marks if it includes any spaces. For example, on Windows if the Thunderbird program is installed on drive F in a folder called "Mozilla Thunderbird" and your profile is located in a folder called "My TB profile", you would use this syntax:
"F:\Mozilla Thunderbird\thunderbird.exe" -profile "F:\My TB profile"
You can launch Thunderbird this way using a command prompt, a shortcut, a batch file, or a JScript (.js) file. See this MozillaZine forum thread for further information and examples.
The key difference between setting up and running Thunderbird in this way and doing so in the "normal" way is that Thunderbird's Profile Manager normally keeps track of your profile(s) using a profiles.ini file stored on the computer's boot drive. For Thunderbird to be used effectively on a USB stick, in a completely portable mode, it obviously cannot rely upon a file stored on one computer's boot drive in this way. The -profile "path" syntax thus provides Thunderbird with a way to find your profile without relying on information normally stored on the boot drive.
Note that you can also use the same syntax, even without a USB drive, to run a profile on your computer that the Profile Manager doesn't know about. This can be useful, for instance, if your profiles.ini file happens to get corrupted or accidentally deleted but the profile itself is intact. It would also be useful for roaming users whose profile was on a file share.
Compacting is automatic in current versions of Thunderbird. (If you set up Thunderbird to store messages on a USB stick, make sure to compact folders periodically. Otherwise, you may find that your mail files on the USB stick are filling up with deleted messages that have not actually been erased from the mail files. Compacting folders will keep the size of your mail files to a minimum.)