Opening tbird from firefox

[Big Weapons]

I'm trying to open Thunderbird from FireFox through the Mail toolbar button [the one that when clicked, a dropdown menu comes down, one of which says "Read Mail"] I'm trying to get tbird to launch after clicking the Read Mail button, but have been unsuccessful as of far. I was able to open outlook through that menu before I uninstalled it. Anyone got any ideas?

[Statica]

What is your default mail program? If it is thunderbird then set it as your default on your computer (Control Panel > Internet Options > Programs > Email > Thunderbird). If it is not on your list, then open Thunderbird and go to Tools > Options > General Settings and check mark - Use Thunderbird as the default mail application.
Once you have done that Tbird will open as default from any mail button.
Right now, since Outlook is set as the default application, when you click the mail button, it's openning up.

[Big Weapons]

It is the default application and it's not working.

[Statica]

Just as a test - what program opens when you click on this link.

[Big Weapons]

Thunderbird opened. I actually uninstalled outlook, so tbird is the only one that should open. Or nothing at all, as the case seems.