This is a test of commonsense. Complete the next sentence:

How to send an email at a specific time in the future using mozilla thunderbird
Download thunderbird 3.1 + version of the extension.
You will need to save it your hard disk and then install it from thunderbird extension manager.
Instructions for installing :
Right click on the link and choose " save link as..." or " save target as...".
Choose a file path on your hard disk. [ desktop/home folder is fine too].