Awesome Add On Rated 5 out of 5 stars

Thank you, this add-on makes my life a lot easier. I work late at night and don't want my clients getting emails at 3 am so I use Send Later to deliver emails to them during the normal workday. Works great, no issues, love it!

Rated 3 out of 5 stars

I like the functionality. But I dislike the weird design of the dialogue window. Please make it possible to use colours and fonts/font sizes according to current system settings. I believe, the dialogue could be redisigned to look a lot simpler.

This review is for a previous version of the add-on (4.4). 

"Send Later," an essential e-mail business tool Rated 4 out of 5 stars

Few e-mail messages are so urgent that they must be sent immediately. In contrast and often far too often, many e-mail messages are sent before they're error free. With "Send Later" add-on I regularly delay the sending of most of my messages by an hour, so I have an opportunity to grab it back and make corrections, should I later realize a mistake. Most of the time the messages go out without revision, but for those few times when I realize I've made a blunder, "send later" has saved me lots of embarrassment. "Send Later" is a tool that I use every day.

This review is for a previous version of the add-on (4.4). 

Rated 4 out of 5 stars

This looked pretty good at first, but the interface of the schedule dialog could be much clearer. Instead of "send to outbox" and "send now", it should only have a "schedule for send" button. I clicked the "send now" thinking that would send it as a schedule message. An email just went out Friday night instead of Monday morning... Why have a true "send now" button when you wouldn't even use this addon's functionality when sending a regular, non-scheduled email?

reply to @jikamens

Okay, that makes sense. Thanks!

This review is for a previous version of the add-on (4.4). 

Can't please everyone

I have tried various different layouts for the prompt window, and no matter what I do, somebody complains. At some point all that's left to do is to find the interface design that seems to provoke the fewest complaints, and do my best to document it for the few people who are still confused.

I'm not sure how to make it more obvious than it is now -- the "Put in Outbox" and "Send Now" buttons are in an entirely separate box in the dialog, outlined in red, and the button for scheduling a message is labeled "Send Later at time(s) specified above" -- without making the interface more clunky rather than less.

I understand that some people do not find the interface entirely intuitive. That is why there's a user guide as well as detailed, explanatory tooltips that pop up when you hover over the buttons.

The "Put in Outbox" and "Send Now" buttons are there because people use them. "Put in Outbox" is necessary because when Send Later is installed, that button is the only way to put a message into the Outbox. "Send Now" is necessary because some configure their "Send" button to _always_ pop up the Send Later dialog, and they need the option when the dialog pops up of sending the message now rather than scheduling it for later.

Amazing tool Rated 5 out of 5 stars

As a graphic designer I often find myself working really late at night, and nowadays with the help of the smartphones if you send an email at 3 am it's very likely that you wake up your client, also if you send emails at late hours you can send the wrong impression that you are free to work at whatever time they desire, so in order to protect myself and the rest and peace of my clients I started looking for a way to send my emails early in the morning while I'm trying to get 5 hrs of sleep, and I found this amazing add-on, I'm in love with it, just today it help me sent 6 emails at 8 am while I was getting my beauty sleep, xD, download it and try it, you won't regret it!!

This review is for a previous version of the add-on (4.3.1). 

great addon to send mails later Rated 5 out of 5 stars

I really like the functionality, this addon provides. Works great. A big THANK YOU!

This review is for a previous version of the add-on (4.3.1). 

Great product, very helpful Rated 5 out of 5 stars

I have been using this add on for several years and am very pleased with it's functionality and ease of use. It is a nice tool to use to send to people messages when they may get notification at odd hours or if you are up late and don't want to advertise that fact. I have donated to the program and would encourage you to also to keep it being updated and improved.

This review is for a previous version of the add-on (4.3.1). 

Rated 4 out of 5 stars

Very nice! Would be even nicer if I had the option to configure

-Send tomorrow morning at 9:00

With ONE button. I believe I would use it all the time

This review is for a previous version of the add-on (4.2.4). 

See user guide

The user guide ( shows how to set this up.

It does require some manual configuration, but I'm not sure how to avoid that. Everyone wants something slightly different from the add-on, and if I tried to make everything everybody requested point-and-click, the add-on would be too large, unwieldy, and difficult to use.

Very necessary Add-On Rated 5 out of 5 stars

I use Mozilla Thunderbird 24.5.0.
Function "Send Later" was necessary.
IMHO developers Mozilla Thunderbird
it is necessary to add this possibility.
By means of "Send Later 4.2.3" I have solved this problem.
All works perfectly. Five stars from me

This review is for a previous version of the add-on (4.2.3). 

Rated 4 out of 5 stars

is great, but CMD + SHIFT + RETURN (in Mac is command, not control), is hard to remember and not very usable... an icon on the message menu would be great.

Thanks and keep up the great work,


This review is for a previous version of the add-on (4.2.3). 

Great Rated 5 out of 5 stars

Thank you to the developer because this add-on is mandatory for my life. I routinely write messages at 2AM to be sent out during "normal business hours" later that day. I would need to stop using T-Bird if this extension were not available. Frankly I don't know what I would do because no other email client does what I need (Gmail isn't an option).

I haven't had any issues regarding "spamming" or multiple sends. I will update this review if I do. I only have SendLater check the drafts box every 10 or so minutes, however -- not every minute. I don't need to specify the exact time that emails need to be sent. Perhaps changing that default value might help?

I ran T-bird 2.0 for years, then two years ago switched to 3.1, and only a week ago switched to the latest version. I am wary of "upgrades" because my email system needs to be absolutely bomb-proof or I stand to lose a great deal of money. I used the Mail Tweaks "Defer" add-on for years which worked fine, but this seems to have more options and I'm looking forward to integrating it into my business and my life.

This review is for a previous version of the add-on (4.2.2). 

Rated 5 out of 5 stars

Fantastic! One of the best add-ons for Thunderbird!

This review is for a previous version of the add-on (4.2.2). 

Rated 5 out of 5 stars

Genial, habe schon ewig danach gesucht und jetzt gefunden, danke an den Entwickler und weiter so !!!!!
Greats from Berlin

This review is for a previous version of the add-on (4.2.2). 

muy util y practico Rated 5 out of 5 stars

Es una de las extensiones que mas uso, me permite escribir mails en cualquier momento y enviarlos cuando comienza el horario laboral, permite configurar botones por minutos o simplemente ingresar un dia y hora especifico. Hace mas de 1 años que lo uso y jamas me ha fallado.

This review is for a previous version of the add-on (4.2.0). 

Rated 5 out of 5 stars

So easy to use and you can't mess up !


This review is for a previous version of the add-on (4.2.0). 

Rated 4 out of 5 stars

This is something that simply works and works well! Just some improvements needed in the interface, but nothing really important. Donate! It deserves it! I did it :)

This review is for a previous version of the add-on (4.1.7). 

Rated 5 out of 5 stars

Nuff respect! This extension/add-on is exceptional. Works flawlessly so far. I can't send any $$$ unless you will take Jamaican dollars but if you ever come to Jamaica link me and I'll treat you to the best Jerk Pork and Chicken in the world! Thanks for the hard work it is sincerely appreciated.

This review is for a previous version of the add-on (4.1.7). 

bug Rated 5 out of 5 stars

hi,send later don't send "Disposition-Notification-To"and alsoReporting-MTA: dns

I mean that

in these case i ask for reporting ok

when send later is activate i don't have the "reporting mta"
when it is desactivate i have the message
like this :

Reporting-MTA: dns;
Arrival-Date: Mon, 17 Dec 2012 08:06:21 +0100
Original-Envelope-Id: <50CEC44F.2000801@.........................

Original-Recipient: .............@....................
Final-Recipient: rfc822;...........@.................
Action: relayed
Status: 2.0.0
Remote-MTA: smtp..............

i see nothing in the user guide about this.
a bug ?

This review is for a previous version of the add-on (4.1.5). 

See user guide

There is a workaround in the user guide at for the Disposition-Notification-To issue.I'm afraid I don't understand what you mean when you say that the add-on does not support "Reporting-MTA: dns".

As far as I know, "Reporting-MTA" is a header inserted into bounces by mail transfer agents, not one that is meaningful when inserted into a message by a mail client like Thunderbird. Could you clarify?

UPDATE: Aha, I think I understand now. You mentioned "Reporting-MTA: dns" because it is what is inserted into the return receipts you get when you specify Disposition-Notification-To. In that case, my answer above still applies -- please use the workaround in the user guide if you want return receipts for messages sent with Send Later.

Rated 5 out of 5 stars

Nützlich, so lange TB auch zur Sendezeit an ist. ;-) Schön wäre eine Möglichkeit, als Sendezeit einzutragen: "Beim Schließen von TB".

This review is for a previous version of the add-on (4.1.5). 

Solicications are annoying Rated 4 out of 5 stars

This extension used to work great for its intended purpose. Actually, it still does. But lately the extension has started displaying announcements in Thunderbird every time the extension is updated. There is, as far as I can tell, no way to turn off the display of these announcements.

Making matters worse, the announcements invariably include a plea for monetary donations. I fully understand that the software is being provided for free and the author has every right to ask for donations. On the other hand, I have every right to stop using the software, for any reason or even for no reason at all. I have in fact stopped using this extension, because the unpleasant forced advertising outweighs the benefits of the software.

The author should seriously consider removing the forcible display of announcements with each new version update. I cannot see how this behavior is user-friendly in any sense of the term.

EDIT 2012-12-06: Thanks for the response. Let me clarify that the solicitations are a minor issue next to the announcement spam. They are just the straw that broke the camel's back. Certainly reducing the frequency with which release notes are displayed would be an improvement. I have improved my rating based on your doing that.

I do not think that my position is unreasonable. I have upwards of 4000 software packages installed on my computer. On average maybe 5 of them update in a given day. I certainly do not feel like I need to see all the release notes for all my installed software every time they update. All I need is the ability to access the release notes when desired. You say that other extensions do this too, to which I have two replies. First is that the other extensions are wrong as well, and the second is that they often include a way to disable the display of release notes (for example NoScript has a checkbox for this in its preferences pane).

I am not writing this review to save myself any effort. Obviously I could have just uninstalled your extension and continued on with my life. I want to help you improve your software, which is in all other respects excellent, and this is why I take the time to review. I don't think it is in any way unreasonable to allow users to choose whether to see release notes every time or not.

This review is for a previous version of the add-on (4.1.5). 

Release notes

The release notes display with every release because every release contains new functionality that users need to be informed about. Most of the good Firefox and Thunderbird plugins I use display release notes with each release.

However, based on your feedback, it occurs to me that it would be a good idea for me to distinguish between functionality releases which require release notes to be displayed and minor releases which do not. For example, the release that just came out, with a new translation and an updated date-parsing library, probably did not need release notes to be displayed. I have implemented this for the next release of the add-on.

Every add-on that I use that displays release notes has a request for donations on the release notes page. Whether you donate or not is completely up to you; the add-on is free and will remain that way.

The add-on does everything _I_ need it to do and has for quite a while. If I were only maintaining it for myself, then I'd stop spending any time on it and get on with my life. I continue to develop it to benefit its >26,000 users, and I don't see anything wrong with asking those users to send a few bucks my way if they are so inclined. Frankly, I think the offense you take at this is disproportionate and unreasonable.

UPDATE: It was not your comments about the frequency of displaying the release notes that I found unreasonable; it was your comments criticizing the fact that I ask for donations.