double messages

[WINUX]

Hi all

All of a sudden today, Thunderbird was retrieving my mails again. So
now I have alot of messages double and I don't want to delete the
doubles as it would probably get my messages deleted from the hotmail
server. For a few weeks it did work correct.
I use the beta 1.2.25b2 older versions where not working.

Does anyone has an explanation for this?

Thanks in advance

[KE4AVB]

It could been a server when down and MS restored the data from a
backup and some of your emails may have not been read before that
particular back was made. Every once a while I get a few old emails
download again. Hotmail accounts sometimes develop errors and are fix
without you knowing it as it may be affecting more than one person.
Keep receiving your emails and if the dupes are constant then there
maybe problem with webmail addon; otherwise, it may have been failure
on MS side.

If I remember correctly there is several add-ons for removing the
duplicates. Search Thunderbird Extensions for the one you like to try.

Eugene

[alanrf]

Sorry to report that the suggestions made by KE4AVB have nothing to do
with the way things really work (sorry KE4AVB - this is absolutely not
personal but it is technical).

The decision on which messages to download are not made by these
extensions in any way at all. The decision on which messages to
download are made entirely by the main Thunderbird program.

This is how it works. Every time Thunderbird contacts the mail server
its first task is to get a list of every email message held on the
server. These extensions act as a POP server. So the extension gives
to Thunderbird a list of every single email message held on the
server. If you keep your messages on the server then Thunderbird will
have saved the list it got last time (it is called the popstate.dat
file for each POP account). Thunderbird compares the two lists and
for every email it thinkls it has not seen before Thunderbird will ask
for the message to be downloaded. When all the messages have been
downloaded and moved to the Inbox on Thunderbird then Thunderbird will
store the new list (I am leaving out some housekeeping like dealing
with deleted messages but they are not totally relevant at the
moment). The important point to note is that if you terminate
Thunderbird before it has a chance to complete and store the new list
then next time round it will not recognize that *some* messages were
downloaded and start over from the earlier point again.

There is one other more severe condition. If the extension has a
significant problem with the server it can return to Thunderbird a
"null" or empty list. Thunderbird will store that. Next time you
connect to the server successfully and get a good list of the messages
Thunderbird will think that every message is new and will download the
whole of the server's mail contents again.

To the original poster - there are, you know, valuable add-ons to
delete double downloads but you are knowledgeable to beware of the
issue of the undesirable deletion issue. If you plan to use the value
of duplicate deletion then you should temporarily change your option
in Thunderbird to "leave messages on the server" while you use the
extension. I do not know of an add-on that avoids this
need.

[alanrf]

For a classic account of the way it works see the thread
"Hotmail account - inbox emptyed after using webmail exstension"

[KE4AVB]

None taken...but as you wrote if the extension has a serious enough
problem when communicating the site then it could cause the problem.

Can you explain why then Thunderbird after storing the popstate list
would TB redownload messages on the next time after you login via
Hotmail webmail site and mark them as unread? Your explaination is
leading to me think TB is only comparing its list of all messages to
the Hotmail site list would not redownload the messages that it had
already downloaded even though they now mark as unread. Could this be
because get reassigned new id numbers by the hotmail site?

Shouldn't Thunderbird save all it files when it is terminated
properly? example: using either the exit command or close program
check box in the under right. When I write programs that is one of the
first things I do is to have the program check for open files and
close those that left open as the exit section executed. I tried to
close files as they are no longer needed just keep the data safe. I
know if you shutdown Windows or other operating and or simply turn the
computer off then program file may not have been saved.

Eugene

[alanrf]

The Webmail Author has worked very hard to avoid the issue of
returning a null list when contact problems occur - I have been using
these extensions for years and have not seen a case in a few years. I
have seen cases where real POP servers have done this. However, if it
happens then the result is always that the whole Inbox gets downloaded
again.

That is why it is not a good idea to keep very large numbers of mail
in the Inbox on the Web server. It increases the overhead of every
contact and it makes sense, once in a while to move the bulk of the
saved messages to q custom archive folder on the server.

The answer to your question about marking messages as unread on the
Hotmail Web interface is fairly easy.

You have opted to use a feature of the Hotmail extension that, while
useful, is not strictly complying with the POP protocol and it not
without its downside. It is important to note that the POP protocol
has absolutely no recognition of message status on the server as read
or unread. In POP messages exist or they do not and that is the only
status known to the protocol.

Here's how it works when you select that "unread only" option.

When Thunderbird contacts the extension to get the list of messages on
the server the extension only returns a list of the unread messages on
the server to Thunderbird. None of the read messages on the server are
included in the list. So, to be literal about it the extension is
lying to Thunderbird. However Thunderbird downloads those messages as
new and the extension *has* to mark the messages as read on the server
to avoid them being downloaded again on the next contact.

Then there are two possibilities and it would depend on your sequence
of actions (and possibly your Thunderbird settings - like automatic re-
checking after n minutes).

If Thunderbird has contacted the server again to get a new list of
messages then, because the list can only contain unread messages, none
of the recently downloaded messages will appear in the list given to
Thunderbird and Thunderbird has lost all memory of those recently
downloaded messages. If you then go to the Web interface and mark
some of those messages as unread then on the next contact they will
appear as new to Thunderbird and be downloaded again.

If, on the other hand, you terminate Thunderbird after your unread
messages have been read in and then you go to the Web interface then
Thunderbird's memory will be only of the messages just downloaded. If
you now mark those messages as unread and then start Thunderbird again
then those messages will still be in Thunderbird's memory and would
not be downloaded even though they will remain marked as unread on the
Hotmail server. This is a rather artificial case for most users.

Use of the "unread only" option also prevents the ability to have
message deletions in Thunderbird reflected back to the server.
Because it does not comply with the POP protocol and the issues that
can arise I always advise the folks I support not to use this option.

[KE4AVB]

Okay I get it, somewhat. Basically Thunderbird never actually looks at
what it has in it actual email files instead it has a separate file
for doing this. Sounds like that might need to changed in the future
as it makes more sense to me to compare actual stored emails to those
being downloaded from the server, but that is another issue and I will
not pursue it here in the webmail forum as it not related to the basic
subject. Besides it is probably not addressable anyway.

Eugene

[alanrf]

In fact the Thunderbird way works pretty well if the POP protocol is
followed. It is the "bending of the rules" by the extension that
introduces useful features but they come with associated issues.

Thunderbird 3 has no email database redesign. POP3 is not going to de
redesigned - the main thrust will slowly be move towards IMAP. Though
the email database may be redesigned (if Thunderbird continues to be
developed) it is not as simple as "messages stored in the mail
client". One can well say that you want to delete old messages from
the mail client store but that you do not want them to be downloaded
again from the server.

You are quite right though that this is not really and issue for these
add-ons so I agree we should leave it there.

[WINUX]

Sorry for getting back to this so late.

Thanks for your explanation which gives an interesting insight in how
TB and the webmail extensions do work.

I already had the "leave messages on server" option turned on. I am
not sure if I can delete those double messages from the list in
thunderbird directly. I do not want to have any lost messages on the
server! That is the most important. Maybe it is safer and easier to
delete all local content through the filesystem and then configure it
again.
What would you recommend?

I also wonder, if POP3 does not has a message status, why then not
write an IMAP webmail server? Do note that I am not knowing all the
details about those protocols and I don't want to say this is easy to
make... it is just a tought of mine. ;)

Thanks in advance for your answer and time

[Webmail Author]

This extension should clean up your inbox

https://addons.mozilla.org/en-US/thunderbird/addon/4654