(If hidden, click the plus sign next to Local Folders.) The Local Folders' Disk Space settings are an derivative of the Local Folders item in the left pane of the Account Settings window. The email directory is listed under Local Directory, and navigate up two levels. To find the root of your Thunderbird profile directory, go to Tools > Account Settings, and select Local Folders. You can change it, but we don't recommend you do without a good reason, (such as current hard drive or partition critically running out of space). The Local directory input field tells you where your Thunderbird emails and profile are stored. (While useful, enabling this option assumes that you never did -nor will- delete an email mistakenly. You can optionally ask Thunderbird to automatically Empty Trash on Exit by checking the appropriate checkbox. As you can see, this change is visible in Thunderbird's folder pane. In our case, we just renamed our Local Folders Local Emails. The Account Name field lets you give a custom name to your Local Folders.

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