Mozilla Thunderbird lets you go a middle way. You can delete attachments from emails selectively or "detach" them by saving them to a folder on your hard disk while inserting a link to the saved file in the message in place of the original attachment. If that sounds complicated, it's not because it were. Deleting attachments is easy in Mozilla Thunderbird, and it is very useful.
Delete Attachments from a Message in Mozilla Thunderbird
To remove an attachment from an email in Mozilla Thunderbird:
- Click on the attachment you want to delete with the right mouse button.
- Select Delete from the menu.
- Click OK.
Detach an Attachment from an Email in Mozilla Thunderbird
Mozilla Thunderbird can also save the file to disk and replace it with a link to the saved file. The message will still appear to have an attachment, and the link lets you operate on the saved file as if it was still present inside the email, but the disk space in the message store is saved.
To detach a file from the message to which it has been attached in Mozilla Thunderbird:
- Click the desired attachment with the right mouse button.
- Select Detach… from the menu.
- Highlight the folder in which you want the file to be saved.
- Click Choose.
- Click OK or Save.
(Updated April 2013)

