The title to this post might be deceiving, since I am not going to walk you through on how to make Thunderbird portable, but rather how to make Thunderbird portable cross different devices by using a file sharing tool (ie. Dropbox).

Let’s say that you have two Linux, Mac, or Windows machines and would like to have your Thunderbird mailboxes and configurations to be the same.  So, whenever you make a change on one machine, it will synchronize on the other.  Key that you want to consider is how much space your Thunderbird profile is taking and if you will have enough space in Dropbox.

The following was tested in two different Ubuntu Linux machines (I also did it on Windows machines, but the steps below are for Linux).  Here is what you will need to do.

1. Make sure that you have Thunderbird configure the way you want it/like it on PC#1
2. Then close out Thunderbird to make the following changes
3. Go to folder /home/pc1_user/.thunderbird/
   where pc1_user will be change to your actual user profile
4. You will see couple of files and folders in there.  The ones that you will be interested are “profiles.ini” and “randomfoldername.default”
   where “randomfoldername.default” will be something like this “z85gg4eg.default”
5. Move “randomfoldername.default” to your Dropbox account.  In my case I created a folder for Thunderbird where this new folder will be under.
   Here is how it looks… /home/pc1_user/Dropbox/Thunderbird/randomfoldername.default
6. Now, let’s update “profiles.ini”.  Your configurations might look like something like this

   [General]
   StartWithLastProfile=1
   [Profile0]
   Name=default
   IsRelative=1
   Path=randomfoldername.default

   What you are going to do is to make some modifications to this file by changing “IsRelative” and “Path” to look this this

   [General]
   StartWithLastProfile=1
   
   [Profile0]
   Name=default
   IsRelative=0
   Path=/home/pc1_user/Dropbox/Thunderbird/randomfoldername.default

7. Now you should be able to open Thunderbird on the computer with no problem :).  Just note that by doing this doesn’t fix your problem on having Thunderbird synchronized in two computer.
8. You will need to do something similar on PC#2.
   1. Make sure that you have Thunderbird installed
   2. Make sure that you have Dropbox installed
9. Go to folder /home/pc2_user/.thunderbird/
   where pc2_user will be change to your actual user profile
10. You will see couple of files and folders in there.  The one that you will be interested are this time is only the “profiles.ini”.
11. Now, let’s update “profiles.ini”.  Your configurations might look like something like this

    [General]
    StartWithLastProfile=1
    [Profile0]
    Name=default
    IsRelative=1
    Path=randomfoldername.default

    What you are going to do is to make some modifications to this file by changing “IsRelative” and “Path” sections to look this this

    [General]
    StartWithLastProfile=1
    
    [Profile0]
    Name=default
    IsRelative=0
    Path=/home/pc2_user/Dropbox/Thunderbird/randomfoldername.default

12. There you have it!!! Now you can enjoy Thunderbird in two (or many more) machines with the same settings, mailboxes, and configurations.

Sources:
http://kb.mozillazine.org/Running_from_a_USB_drive_(Thunderbird)
http://www.makeuseof.com/tag/access-your-personalised-thunderbird-client-on-any-computer-worldwide/

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