Excellent tool Rated 5 out of 5 stars

I can finally suppress those nasty doubles!

The add-on is simple to use and efficient. However, I suggest adding a "do the same for all folders" option when suppressing messages to go faster: I have many folders, and having to confirm the suppression for each of them is kind of a pain. This option would make the add-on complete!

Rated 5 out of 5 stars

This add-on is extremely helpful when you end up with duplicate messages in your mailbox (for example as a consequence of communication problems between Thunderbird and an IMAP server). Straight forward and quick.

Works well, but needs some tidying up to be somethign you can keep. Rated 3 out of 5 stars

This add-on adds a ridiculously long option to the right click and Tools menus so it needed removing as soon as I had used it. This may be why I removed it last time I used it.

For removing duplicates it works well.

Couple of minor annoyances which I found while I had it installed (for less than 5 minutes due to the above), telling it to search special folders gives you an error about not searching special folders, which is set in the global options. I can understand the behaviour if you were selecting the root of the account and searching everything but it shouldn't do this if you are specifically selecting a special folder only.

Once you have searched for duplicate messages and you select delete on the duplicate messages window you get a pop up confirmation. If you select cancel rather than dropping you back to the results window it just cancels the whole process and you have to start again.

This review is for a previous version of the add-on (0.3.10). 

Some replies

* About the cancel-cancels-everything - you're right, it shouldn't work that way. I opened a bug and will fix it:
https://www.mozdev.org/bugs/show_bug.cgi?id=25978

* About the long right-click menu item: I'm not too happy with it myself, but - can you suggest something shorter? I don't want it to be cryptic and confusing.

* About the special folders restriction: In this case I have to respectfully disagree. You need to remember that user error with this extension can lead to Data Loss; as a result, I have to "err on the side of caution" - I remember the cases of people complaining about accidentally deleting messages from Sent / Drafts / etc.

Anyway, thanks for taking the time to write a detailed review.

重複メッセージの処理(削除)から解放される最良のアイテムとして、推奨します。 Rated 5 out of 5 stars

素晴らしい!
簡単です。そして、確実(Perfect )に機能します。

(同様な機能を提供する「Remove Duplicate Messages」を使用をしていたが・・・)、この「Remove Duplicate Messages (Alternate)」では、①削除前に検索結果を表示できるうえ、②default 設定で、(重複メッセージの処理を)「完全削除」と「ゴミ箱へ移動」の二択から選択することができるので、(不意な削除を防止でき)安心です。③しかも IMAP and RSS accounts も管理ができるので万能です。

多言語(日本語)対応がなされ、機能に不足は無く、且つシンプルに構成されているので、解りやすく、スキル(技量)を問わずに簡単に使いこなすことができます。
重複メッセージの処理(削除)から解放される最良のアイテムとして、推奨します。

This review is for a previous version of the add-on (0.3.10). 

Rated 5 out of 5 stars

Very useful extension but beta version 0.3.11b is required for all functions to work in current Thunderbird version.

This review is for a previous version of the add-on (0.3.10). 

Great addon, but stopped working for TB 31 Rated 5 out of 5 stars

Thanks eyalroz for this very useful addon. It seems to have stopped working in the latest updated of TB - 31.

This review is for a previous version of the add-on (0.3.9). 

Fixed in 0.3.10b

Fixed - please check the beta.

Seems to have stopped working in TB 31.0 Rated 4 out of 5 stars

Great addon, but doesn't find anything since I upgraded to TB 31.0
Edit: Dev version doesn't work either

This review is for a previous version of the add-on (0.3.9). 

Fixed in 0.3.10b

Fixed - please try the beta

Geweldige add on Spaart heel veel tijd Rated 5 out of 5 stars

Ik had wat zitten rommelen en had honderden dubbele mails. In eer minuten weggewerkt!

This review is for a previous version of the add-on (0.3.9). 

Rated 5 out of 5 stars

2001 duplicated mails deleted :-D
Thanks a lot! I can't recommend this addon enough!

This review is for a previous version of the add-on (0.3.9). 

Rated 5 out of 5 stars

1921 duplicates found, thanks for the tool

This review is for a previous version of the add-on (0.3.9). 

Rated 5 out of 5 stars

It does not work with Thunderbird 29.0a2.
Folder -> Remove Duplicates...
[JavaScript Application]
Not searching special folders.

This review is for a previous version of the add-on (0.3.9). 

Fixed in 0.3.10b

Try the beta please.

Rated 5 out of 5 stars

100s of duplicates after transferring 4 accounts from one provider to another. This smart little addon found them. Great Tool!

This review is for a previous version of the add-on (0.3.9). 

Muy bueno Rated 5 out of 5 stars

Cumple muy bien su función y es fácil de usar.

This review is for a previous version of the add-on (0.3.9). 

One of the "Must Have" addon Rated 5 out of 5 stars

I can not thank developer enough for making such a useful addon. Only if there was a way to operate this addon through windows command line/cmd.exe, it would make life much much more simpler

This review is for a previous version of the add-on (0.3.9). 

Command-line operation

You are possibly looking for something like mbox-tools:
https://github.com/np/mbox-tools
which operates on Thunderbird's (highly dated) mail storage backend. I'm not sure if mbox-tools has dupe culling, though.

Rated 5 out of 5 stars

Version 0.3.9b - icons look good :)
But I cannot switch on search in special folders in option - any mark do not do it.

This review is for a previous version of the add-on (0.3.7). 

Please file a bug report

Please file a bug report at http://www.mozdev.org/bugs/ with the exact phenomenon you're seeing, and exactly what you tried to do and didn't work.

problems with the new version 24 Rated 4 out of 5 stars

There are some compatibility problems in the new version of thunderbird 24 solve them as soon as possible!

This review is for a previous version of the add-on (0.3.7). 

Workaround in 0.3.8 and fix in 0.3.9b - try it

See bugs:
https://www.mozdev.org/bugs/show_bug.cgi?id=25546
https://www.mozdev.org/bugs/show_bug.cgi?id=25574

Worked perfectly Rated 5 out of 5 stars

Cleaned up all the duplicates very efficiently.

This review is for a previous version of the add-on (0.3.7). 

Works perfectly Rated 5 out of 5 stars

The key to making this add-on work perfectly is to adjust the comparison criteria so that you know the messages that match are truly the same as each other in spite of having small differences in the body, which can happen. Thus the number of lines could be SLIGHTLY different and the size might also. For example, you might have an extra NULL in one, or an extra <LF>. Make sure you have enough criteria so you are confident of the found matches. The tool is great.

This review is for a previous version of the add-on (0.3.7). 

Does the job, quickly and accurately Rated 5 out of 5 stars

Like the title says. Does what it's supposed to, and more quickly than expected.

This review is for a previous version of the add-on (0.3.7). 

Update of prior review Rated 4 out of 5 stars

After some experimentation, resolved the problem I experienced in my previous review. And as a result, upped the rating to 4/5 stars. Not 5 stars as that problem and its work-around are not obvious.

The problem is that when you first install the addon and try to use it (either before or after restarting Thunderbird 17.0.x), it does not detect POP account "Trash" folders properly.In the Duplicate Messages Deletion window that appears after detecting dups, at the bottom are the choices "Delete permanently" and "Move to...(drop down list of folder choices)". "Move to..." defaults to "Trash". But leaving that choice alone, it will not properly detect the Trash folder on the account you are detecting dups on, unfortunately. Which means dup messages get permanently deleted, even if you don't want them to be.

To avoid this problem, you first have to open the drop down list beside "Move to..." and manually select the Trash folder for the account you are detecting dups on. Then and only then will your dup messages get properly sent to Trash. In the future it will remain properly selected, so you only have to do it once. Don't know if you have to manually change it for every account you are working on, but I do so to be safe.

This is still a problem and still needs fixing, but at least there is a way around it until its fixed.

EDIT: replying to the author response below. Thanks for the response, but unfortunately you totally misunderstand what the problem is. I elaborated more in my original review linked to at the bottom of this post; might want to look at it.

The problem has _nothing_ to do with "detecting duplicates in trash". The problem is when detecting duplicates in the INBOX of a selected account, the "Move To..." selection defaults to "Trash" (of that account). And by default, it doesn't actually move your messages to there as you would expect. It instead wrongly permanently deletes them.

To work around this problem, you must manually select the "Move To..." folder (Trash or otherwise) for each account in the drop down list.

If you don't do that and instead rely on the default "Move To...Trash" location without adjusting anything manually, your mail gets permanently deleted out of the Inbox when you didn't want it to after pressing "OK". That's the problem.

This review is for a previous version of the add-on (0.3.7).  This user has a previous review of this add-on.

It is 'proper' not to find dupes in the Trash

Practically all users expect Trash folders to be skipped when looking for duplicates. This is both because dupes are usually deleted to the trash (incl. manual deletion), and because, more generally, whatever's in the trash is already not really part of your mailbox, it's deleted-but-undisposed-of. So, it would certainly not be a good idea to change this default behavior.

I understand you might like/expect something different, but you must recognize you're in the minority. For you (and others), there's the preferences dialog with which you can change such settings.