This post has been replaced for Thunderbird and Windows 10.
I have a number of different mail accounts which I read using Mozilla Thunderbird. Each time a new account is added it appears at the bottom of the mail list. One new account I wanted to move near the top, but Thunderbird does not give an option to reorder accounts. The answer is to edit prefs.js file. On Linux systems
~/.thunderbird/<your profile>/prefs.js, and for Windows
C:Documents and Settings[User Name]Application DataThunderbirdProfiles<your profile>pref.js
Look for a line like:
This is the line you will need to modify.
So what does account3 mean and which email account does it match?
In the lines above you will find something like:
user_pref("mail.account.account3.identities", "id2");. If the id was 2, search in the prefs.js file for
user_pref("mail.identity.id2.useremail". This will give you the matching email address.
One little extra if you wish to make a certain email address at the top. It needs to be made the default. See the line starting with:
Remember, only edit this file while Thunderbird is closed.