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Cannot Send Messages (Send Button Does Nothing)

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  • 16 have this problem
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  • Last reply by halmai

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Yesterday morning, I was sending messages fine. Later in the day, when I started Thunderbird again, it took me to a "what's new in 45.0" tab, which implies that it auto-upgraded to 45.0. After closing this tab and going to reply to a message, I learned that I could no longer send messages. Nothing changed except for the automatic upgrade. I learned this while trying to reply to an e-mail. I typed it and hit CTRL+Enter and nothing happened. I figured something had changed, so I hit the Send button and nothing happened. I also tried File -> Send and File -> Send Later with the same lack of any results at all. I restarted Thunderbird and changed the sending account to no avail. This morning, I tried a quick new message using the compose button. On a new blank message with no recipients, the send button is greyed out, but as soon as a recipient is added, the send button turns clickable (as it was in all previous attempts), but still I can't send.

Yesterday morning, I was sending messages fine. Later in the day, when I started Thunderbird again, it took me to a "what's new in 45.0" tab, which implies that it auto-upgraded to 45.0. After closing this tab and going to reply to a message, I learned that I could no longer send messages. Nothing changed except for the automatic upgrade. I learned this while trying to reply to an e-mail. I typed it and hit CTRL+Enter and nothing happened. I figured something had changed, so I hit the Send button and nothing happened. I also tried File -> Send and File -> Send Later with the same lack of any results at all. I restarted Thunderbird and changed the sending account to no avail. This morning, I tried a quick new message using the compose button. On a new blank message with no recipients, the send button is greyed out, but as soon as a recipient is added, the send button turns clickable (as it was in all previous attempts), but still I can't send.

Chosen solution

This morning, I started in safe mode and was able to send. I looked at my Add-Ons and one of them is "EditSender" which apparently doesn't get along with the new built-in feature. Disabling that add-on resolves the problem. I wanted to post the problem and answer separate anyway in case anyone else comes across this.

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Chosen Solution

This morning, I started in safe mode and was able to send. I looked at my Add-Ons and one of them is "EditSender" which apparently doesn't get along with the new built-in feature. Disabling that add-on resolves the problem. I wanted to post the problem and answer separate anyway in case anyone else comes across this.

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The same issue has happened to me as well, right after I installed TB Version 45.2.0. But, contrary to the previous comments, the same happened if I restarted TB after disabling all addons. Disabling the addons didn't solve the problem.

Maybe I can add some more information. Here are the steps I did: - launch TB - compose reply to an incoming mail - press the Send button in the toolbar (nothing happens *) - cut the content of the response to the clipboard for later use - close the main composing window (not the whole TB) - an error message appears saying that TB is busy by sending an email

This error message is pretty strange but can be clear as soon as we check what the Error Console show. After that:

- cancel the above error message - Turn the Error Console on (Tools => Error Console from the main TB menu, not from the menu of the mail composer) - press the Send button again

Now you can see what the problem is. The following message appears there in the Error Console:


Timestamp: 2016.08.19. 23:32:52 Error: GenericSendMessage FAILED: TypeError: msgWindow is undefined Source File: chrome://messenger/content/messengercompose/MsgComposeCommands.js Line: 2854


If you see the source code of the mentioned MsgComposeCommands.js then you can see that the error message about still sending the email is a lie. The problem is that the sending has been interrupted. In normal case a flag is set before sending the mail and is removed when the sending was successful. In abnormal case, however, the process gets interrupted before the flag would be reset. Thus, it will never be re-set.

The only solution I found is to - store the newly composed email on the clipboard, - interrupt the mail sending by enforcing to close the composing window - start a new mail composer window by replying the email again - paste the previous mail body into the new mail - the Send button should work now. If not then repeat the copy to clipboard-close-reply again-paste cycle again.

I am not saying this is the solution. This is just a work-around. The developers should fix this bug, I think.