This article explains how to delete spam or other email messages from your Thunderbird email account without using the Trash. This is especially important if you suspect that the message contains a virus. Instructions apply to Thunderbird or Netscape email.
How to Delete and Remove an Email Account in Mozilla Thunderbird
Normally, when you click the Delete button, the email message is moved to the Trash folder and remains there until you manually empty the Trash or until it is automatically deleted, depending on your settings. (Look in Account Settings > Server Settings and Message Storage to see what your settings are.)
To immediately and irreversibly delete a message in Mozilla Thunderbird, Netscape or Mozilla:
Open the email client.
