So you want a sound to play when you get a new message? Start by going to Thunderbird > Preferences (or on Windows – Tools > Options).
On the general tab, towards the bottom, there’s a section that talks about “When new messages arrive; check the option that says “Play a sound”.
Of course, you’ll want to specify which sound you want to play, so you’ll need to hit that “Advanced” button also. This will take you to the Advanced Sound Options screen.
Here, you can either:
a) have it play a system sound (which depends on what type of operating system you’re running, Windows or Mac)
b) have it play a custom sound.
If you want to pick a custom sound, click the “Custom .wav file” radio button and then click the “Browse” button. This will allow to poke through your hard drive to find the file. Keep in mind, the file has to be a .wav file though, no MP3′s. You can change the file type inside iTunes, but that’s another tutorial!
Once you’ve found the sound you want, click on it and click the “Open” button. The name of the file will appear in that text box under “Custom .wav File”. You can preview the sound, if you wish, by hitting the “Preview Sound” button. That should play the sound that will play when you receive a new message.
Unfortunately, Thunderbird on the Mac has a minor bug that doesn’t allow it to control what sound it played when new messages arrive. So, the way to get around this is to setup the same sound in Apple’s Mail program, then set it up in Thunderbird too. Here’s the instructions for that:
Open Mail (Hard Drive > Applications > Mail), and go to the preferences (Mail > Preferences). As you can see by the pic to the left, the third drop menu from the top allows you to pick a sound. Click on that drop menu and then pick “New Mail Sound”. This will open a Finder window and allow you to pick a sound file, again only .wav files. Find it and hit the “Open” button. The file will show up in this “New Mail Sound” list and you can choose it here.
Once you’ve set that sound in Mail, go back to Thunderbird and change the sound, just like above.