Duplicate emails from POP3

[Niki Estner]

Hi there,

Outlook 2003 keeps downloading all mails from my POP3 account again and
again.

I've found serveral posts on this topic, so this seems to be a common
problem. Is there a common solution?

I already installed the hotfix (Q885243), disabled my email-virus scanner,
and uninstalled all Outlook plugins.

Can anyone help me?

Niki

 

[Jeff Stephenson [MSFT]]

Hi there,

Outlook 2003 keeps downloading all mails from my POP3 account again and
again.

I already installed the hotfix (Q885243), disabled my email-virus scanner,
and uninstalled all Outlook plugins.

How many email accounts do you have? Could you turn on diagnostic logging
(see http://support.microsoft.com/default.aspx?scid=kb;en-us;Q300479) and
post the OPMLog.log file after you've done at least two send/receives and
get duplicates?

 

[Jeff Stephenson [MSFT]]

On Mon, 21 Feb 2005 11:11:57 +0100, Niki Estner wrote:

I haven't had a chance to look over this logfile thoroughly yet. I hope to
have done so by tomorrow...

 

[Jeff Stephenson [MSFT]]

On Mon, 21 Feb 2005 11:11:57 +0100, Niki Estner wrote:

I haven't had a chance to look over this logfile thoroughly yet. I hope to
have done so by tomorrow...

Hi Niki,

It looks to me as if this is a problem on your mail server rather than with
Outlook. From the logs, there were 11 messages sitting in your
pop.1und1.com mailbox, then they went away, then they came back. When they
went away, Outlook removed the entries for the messages from its knowledge
of which messages it had downloaded, because they were gone. So when they
came back, it appeared to Outlook as if they were new and it downloaded
them again.

I wonder - I've seen some posts in the groups that indicate that with some
ISPs, marking a message as 'read' in a webmail interface or via an IMAP
account makes them unavailable to POP3 download. So maybe if the messages
got marked as 'read' through webmail, then marked as 'unread' again, you
could see this behavior where the messages seem to disappear and then
reappear. Could this have happened?

Relevant sections from the logfile, in case you want to bring this up with
your ISP and ask them what's going on:

This shows that there were 11 messages in the mailbox at 10:26:49:

2005.02.21 10:26:49 POP3 (pop.1und1.com): <rx> +OK pt33853764-2's mailbox
has 11 messages (107105 octets) H mstoreng20
2005.02.21 10:26:49 POP3 (pop.1und1.com): Authorized to host
2005.02.21 10:26:49 POP3 (pop.1und1.com): Connected to host
2005.02.21 10:26:49 POP3 (pop.1und1.com): [tx] STAT
2005.02.21 10:26:49 POP3 (pop.1und1.com): <rx> +OK 11 107105
2005.02.21 10:26:49 POP3 (pop.1und1.com): [tx] UIDL
2005.02.21 10:26:49 POP3 (pop.1und1.com): <rx> +OK
2005.02.21 10:26:49 POP3 (pop.1und1.com): <rx> 1 0MKsUu-1D1oWZ2wm3-0000t6
2005.02.21 10:26:49 POP3 (pop.1und1.com): <rx> 2 0MKpdM-1D1q0x4B8x-000562
2005.02.21 10:26:49 POP3 (pop.1und1.com): <rx> 3 0MKt64-1D22hV1pMU-0003Us
2005.02.21 10:26:49 POP3 (pop.1und1.com): <rx> 4 0MKqIe-1D2BKE03BY-000269
2005.02.21 10:26:49 POP3 (pop.1und1.com): <rx> 5 0MKpIi-1D2AqM3P0f-0001Rt
2005.02.21 10:26:49 POP3 (pop.1und1.com): <rx> 6 0MKsUu-1D2KCv2X17-0004w8
2005.02.21 10:26:49 POP3 (pop.1und1.com): <rx> 7 0MKt1w-1D2Sjr0DJv-0006yh
2005.02.21 10:26:49 POP3 (pop.1und1.com): <rx> 8 0MKqlY-1D2Wdw0HiI-0001R8
2005.02.21 10:26:49 POP3 (pop.1und1.com): <rx> 9 0MKqpg-1D37ep22Q7-0002Pq
2005.02.21 10:26:49 POP3 (pop.1und1.com): <rx> 10 0MKqpg-1D38oH4904-0000Ev
2005.02.21 10:26:49 POP3 (pop.1und1.com): <rx> 11 0MKt1w-1D39ZQ1xO1-0005eM
2005.02.21 10:26:49 POP3 (pop.1und1.com): <rx> .

Then, at 10:27:24, there were no messages:

2005.02.21 10:27:24 POP3 (pop.1und1.com): <rx> +OK pt33853764-2's mailbox
has 0 messages (0 octets) H mstoreng37 E MB
2005.02.21 10:27:24 POP3 (pop.1und1.com): Authorized to host
2005.02.21 10:27:24 POP3 (pop.1und1.com): Connected to host
2005.02.21 10:27:24 POP3 (pop.1und1.com): [tx] STAT
2005.02.21 10:27:24 POP3 (pop.1und1.com): <rx> +OK 0 0

Then, at 10:28:18, the messages were back:

2005.02.21 10:28:18 POP3 (pop.1und1.com): <rx> +OK pt33853764-2's mailbox
has 11 messages (107105 octets) H mstoreng10
2005.02.21 10:28:18 POP3 (pop.1und1.com): Authorized to host
2005.02.21 10:28:18 POP3 (pop.1und1.com): Connected to host
2005.02.21 10:28:18 POP3 (pop.1und1.com): [tx] STAT
2005.02.21 10:28:18 POP3 (pop.1und1.com): <rx> +OK 11 107105
2005.02.21 10:28:18 POP3 (pop.1und1.com): [tx] UIDL
2005.02.21 10:28:18 POP3 (pop.1und1.com): <rx> +OK
2005.02.21 10:28:18 POP3 (pop.1und1.com): <rx> 1 0MKsUu-1D1oWZ2wm3-0000t6
2005.02.21 10:28:18 POP3 (pop.1und1.com): <rx> 2 0MKpdM-1D1q0x4B8x-000562
2005.02.21 10:28:18 POP3 (pop.1und1.com): <rx> 3 0MKt64-1D22hV1pMU-0003Us
2005.02.21 10:28:18 POP3 (pop.1und1.com): <rx> 4 0MKqIe-1D2BKE03BY-000269
2005.02.21 10:28:18 POP3 (pop.1und1.com): <rx> 5 0MKpIi-1D2AqM3P0f-0001Rt
2005.02.21 10:28:18 POP3 (pop.1und1.com): <rx> 6 0MKsUu-1D2KCv2X17-0004w8
2005.02.21 10:28:18 POP3 (pop.1und1.com): <rx> 7 0MKt1w-1D2Sjr0DJv-0006yh
2005.02.21 10:28:18 POP3 (pop.1und1.com): <rx> 8 0MKqlY-1D2Wdw0HiI-0001R8
2005.02.21 10:28:18 POP3 (pop.1und1.com): <rx> 9 0MKqpg-1D37ep22Q7-0002Pq
2005.02.21 10:28:18 POP3 (pop.1und1.com): <rx> 10 0MKqpg-1D38oH4904-0000Ev
2005.02.21 10:28:18 POP3 (pop.1und1.com): <rx> 11 0MKt1w-1D39ZQ1xO1-0005eM

 

[Niki Estner]

Hi Niki,

It looks to me as if this is a problem on your mail server rather than
with
Outlook. From the logs, there were 11 messages sitting in your
pop.1und1.com mailbox, then they went away, then they came back. When
they
went away, Outlook removed the entries for the messages from its knowledge
of which messages it had downloaded, because they were gone. So when they
came back, it appeared to Outlook as if they were new and it downloaded
them again.

I will forward your answer to my ISP; Do you have an explanation why I never
got duplicates with Outlook Express? (I switched to OE for a few days,
because I just got too many duplicates)

I wonder - I've seen some posts in the groups that indicate that with some
ISPs, marking a message as 'read' in a webmail interface or via an IMAP
account makes them unavailable to POP3 download. So maybe if the messages
got marked as 'read' through webmail, then marked as 'unread' again, you
could see this behavior where the messages seem to disappear and then
reappear. Could this have happened?

No, I didn't use any other email program or webmailer during that time, as I
expected this could cause problems.

Relevant sections from the logfile, in case you want to bring this up with
your ISP and ask them what's going on:
...

Thank you, maybe my ISP can help.

Just curious: If I got you right, Outlook deletes old email IDs from it's
"do-not-download-again"-list as soon as the POP3 server doesn't send them
again. Wouldn't it be possible (to fix this kind of problem) to store them
longer? I mean, I usually store the whole message on my HDD, so additionally
storing the ID for a longer time (e.g. a year) shouldn't really be a
problem?

Niki

 

[Jeff Stephenson [MSFT]]

I will forward your answer to my ISP; Do you have an explanation why I never
got duplicates with Outlook Express? (I switched to OE for a few days,
because I just got too many duplicates)

No, other than perhaps while you were using OE the server problem didn't
happen, or perhaps OE handles the IDs differently than Outlook does. One
thing I did notice in the logs is that the interval between checks is very
short (about a minute?). Was that just for testing, or is that your
setting? You might try a longer interval (what interval did you use in
OE?), just in case frequent checks confuse your ISP's server.

Just curious: If I got you right, Outlook deletes old email IDs from it's
"do-not-download-again"-list as soon as the POP3 server doesn't send them
again. Wouldn't it be possible (to fix this kind of problem) to store them
longer? I mean, I usually store the whole message on my HDD, so additionally
storing the ID for a longer time (e.g. a year) shouldn't really be a
problem?

This would definitely decrease download performance, as the bookkeeping on
such a large list of IDs would start taking time if you had a year's worth
of IDs. Outlook sorts the list, and also needs to check to see if a
particular ID of a message on the server is in the list - both take
essentially no time at all now, but would start to slow things down with a
year's worth of IDs. Further, while the IDs the server are supposed to be
unique (i.e. an ID only ever gets assigned to a single message), I frankly
don't trust all servers to manage to guarantee uniqueness over a long
period of time (some of them have uniqueness problems already). Non-unique
IDs also lead to duplicate downloads.

The problem really is on your ISP's server, and they need to fix it.