I have no send button therefore can not send messages
I have no send button on: Write, Draft or Reply screens. I had a "send" button before but it appears I lost it when I upgraded software to a newer version i.e., later version download.
Opaite Mbohovái (1)
have you tried right clicking the toolbar, select customize and choosing "restore default set?
Have you tries holding the shift key while starting Thunderbird to see if it might be an add-on?