As many people, I too have several email accounts. Until now, I have been using Thunderbird for my main account, and either used web interface for the other accounts, or used other email clients (Sylpheed, Balsa, ...). For some reason, I never liked the idea of having separate, independent accounts integrated in one email client, perhaps because the added complexity and possibility of confusion. When I used three different email clients, I had three truly independent email accounts.

The only disadvantage is, the other (non-Thunderbird) email clients never worked as well as Thunderbird.

Now I am wondering whether there is a possibility to use three independent instances of Thunderbird, so that I don't have to use inferior email clients.

I know that when Thunderbird is already running, I cannot start another instance. Also, any additional instance would need its own (independent) config directory.

Is there any way to achieve this?

I am using Thunderbird (Icedove 24.6.0) on Debian Wheezy


I have found this article on MozillaZine, which suggests to use the -no-remote option and does not mention the option -new-instance at all.

The man page lists both options, but does not explain what the difference is, if -new-instance is implied when -no-remote is used, or whether they should both be used at the same time.

thunderbird -P "profile_name" -no-remote
thunderbird -P "profile_name" -new-instance

Side note:

The refered article also says, that:

Multiple instances is intended for debugging, so use it at your own risk

Well, I don't intend to use it for debugging, I want to use it for my work. What can possibly go wrong when using multiple instances? How can I mitigate that danger?


You can start Thunderbird from the commandline with the -P <profile> option to specify a different profile. Within the different profiles you have complete seperation. IIRC specifying a profile implies the -new-instance option when starting thunderbird but if not, just add it.

To create a new profile start thunderbird from the commandline with:

thunderbird -ProfileManager -new-instance

On the other hand, have you tried using the IMAP protocol? This gives me completely different trees of folders one for each account that I have in (one) Thunderbird session. Unless I actively copy messages from one account to the other everything stays separate and as long as you close the tree of the account your are not working on, things should not be confusing.

| improve this answer | |
  • is it -new-instance with Thunderbird? the Firefox argument is --no-remote (and it is not implied by -P). – strugee Jul 10 '14 at 19:05
  • 1
    @strugee I did thunderbird --help that gives -new-instance Open new instance, not a new window in running instance. I thought it was implied, as otherwise I think you would have to switch profiles as I don't recall Thunderbird being able to handle two at a time in one session. – Anthon Jul 10 '14 at 19:37
  • 1
    @Anthon - If the second profile does not exist, is there a way to create it? – user1968963 Jul 10 '14 at 20:08
  • @user1968963 start with thunderbird -ProfileManager – Anthon Jul 10 '14 at 20:58
  • @Anthon - in the man page, there is also an option -no-remote: Do not connect to a running Thunderbird instance. What is the difference between -new-instance and -no-remote? Should I use both? – user1968963 Jul 11 '14 at 7:39

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.