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How are messages flaged as "already poped"

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Roger

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May 29, 2008, 4:58:18 PM5/29/08
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I move my Outlook 2000 info from one computer to another by copying the
outlook.pst file to a flash drive and then copying onto the other computer.
I prefer doing it this way, rather than just configuring Outlook to use the
flash drive, because the machine I am leaving is still usable.

Mostly this works well, I always have my messages, contacts etc but
sometimes, after making this move, Outlook wants to download all the
messages on my pop server, even those that have been already received.

Is there some way I can flag messages in the Inbox as having already been
poped? How does Outlook keep track of which messages it already has and
which are new?

--
Roger Sipson

VanguardLH

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May 29, 2008, 8:45:51 PM5/29/08
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"Roger" wrote in <news:uHMD$6cwIH...@TK2MSFTNGP02.phx.gbl>:

On the mail server, POP doesn't keep track of what is new or old. There
is no such concept as new or old. The only concept is exists or not.
POP commands only let you retrieve a list of message in your mailbox.
POP only knows about a mailbox, one container, in which are all your
messages. It has no concept of folders (so the Inbox you see when using
the webmail interface is the mailbox that POP works with). All POP can
do is look into the bucket to see if there are any marbles inside it.
It can't tell which marbles you touched previously. When your e-mail
client asks for a list of messages, that is all it can ask for. It
cannot ask for new messages because there is no concept of new or old in
the list. The LIST command will list all messages in your mailbox.

It is up to the e-mail client to save a history of which e-mails it has
received before. This is a bit difficult if your mailbox doesn't add a
unique hash value to each message. If they are just indexed (1, 2, 3,
and so on) and then you delete #1 then they all shift up. By have the
hash value, called the unique ID, for each message, the e-mail client
can send a UIDL command to get the same list of indexed messages (which
includes the size and why LIST gets send) but each will have a unique ID
to identify it. So later when the e-mail client connects to that same
mailbox, and based on the UIDs that it recorded for prior mail sessions,
the e-mail client can determine which messages are new compared to its
prior mail sessions. It is the e-mail client that dictates whether a
message is new or not.

I don't know if the UID history is saved in the .pst file. An MVP might
be able to state where the UID history is saved. If it isn't in the
.pst file then each e-mail client would think every message is sees
(that it didn't see before) was new. When reading your POP mailbox with
one e-mail client, the messages get marked as retrieved in that e-mail
client, but the other e-mail client has no way to know the first e-mail
client saw those messages.

Diane Poremsky {MVP}

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May 29, 2008, 11:43:21 PM5/29/08
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The message list is stored in a file on the hard drive in Outlook 2000 and
its linked to the acct in outlook on that machine so you can't copy it to
another computer. Newer versions store this file as a hidden message in the
pst, but again, its tied to the acct via a GUID so you can't use it on other
computers. If the second machine does something to delete this hidden
message then the first machine may re-download the messages.


--
Diane Poremsky [MVP - Outlook]
Author, Teach Yourself Outlook 2003 in 24 Hours
Need Help with Common Tasks? http://www.outlook-tips.net/beginner/
Outlook 2007: http://www.slipstick.com/outlook/ol2007/

Outlook Tips by email:
dailytips-sub...@lists.outlooktips.net
Subscribe to Exchange Messaging Outlook newsletter:
EMO-NEWSLETTER-S...@PEACH.EASE.LSOFT.COM

Outlook Tips: http://www.outlook-tips.net/
Outlook & Exchange Solutions Center: http://www.slipstick.com


"Roger" <x@y> wrote in message news:uHMD$6cwIH...@TK2MSFTNGP02.phx.gbl...

Brian Tillman

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May 30, 2008, 7:51:52 AM5/30/08
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VanguardLH <V...@nguard.LH> wrote:

> I don't know if the UID history is saved in the .pst file.

If I recall, for Outlook 2000, it was stored in the registry. I believe for
OL 2007 it's a hidden message in the PST that's usable only by the Outlook
instance that wrote it.
--
Brian Tillman [MVP-Outlook]

Diane Poremsky {MVP}

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May 30, 2008, 11:15:24 AM5/30/08
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Nah, it is stored at C:\Documents and Settings\username\Application
Data\Microsoft\Outlook\MSIN*.RHC in windows xp.

It's tied to the computer GUID though, so you can't move it.

--
Diane Poremsky [MVP - Outlook]
Author, Teach Yourself Outlook 2003 in 24 Hours
Need Help with Common Tasks? http://www.outlook-tips.net/beginner/
Outlook 2007: http://www.slipstick.com/outlook/ol2007/

Outlook Tips by email:
dailytips-sub...@lists.outlooktips.net
Subscribe to Exchange Messaging Outlook newsletter:
EMO-NEWSLETTER-S...@PEACH.EASE.LSOFT.COM

Outlook Tips: http://www.outlook-tips.net/
Outlook & Exchange Solutions Center: http://www.slipstick.com


"Brian Tillman" <tillm...@yahoo.com> wrote in message
news:OEn76wkw...@TK2MSFTNGP05.phx.gbl...

VanguardLH

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May 30, 2008, 1:34:22 PM5/30/08
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"Diane Poremsky {MVP}" wrote in
<news:5ED0B30D-8D70-4DBD...@microsoft.com>:

<slightly modified to use %userprofile% instead of the literal path>
> Nah, it is stored at:
>
> %userprofile%\Application Data\Microsoft\Outlook\MSIN*.RHC

>
> in windows xp. It's tied to the computer GUID though, so you can't move it.

Must be an OL2007 thing, then. I don't have that file for OL2002. The
only files that I have there are:

outcmd.dat 11KB (Outlook config data)
outlook.fav 24KB (Outlook Bar shortcuts)
outlook.nk2 70KB (nicknames)
outlook.srs 4KB (send/receive settings)
outlprnt 38KB (print settings)

I search my entire C: drive for *.rhc files (using Agent Ransack so I
don't run into Microsoft's screwup in the search they crippled in
Windows XP) and found no matching files. Also, the per-user session
data is stored under:

%userprofile%\Local Settings\Application Data\Microsoft\Outlook

That is where are my .pst files. There are some other files but they
are too small to be holding UIDs for every e-mail that I have ever
received into Outlook ever since MS Office XP got installed many years
ago. UIDs are to remain unique throughout the lifetime of an e-mail
account as per RFC.

There is an outlook.nst file under this local settings subfolder. I
suspect it was created when I tested the Outlook Connector plug-in (but
found out it won't work with OL2002).

So, so far, for OL2002, I haven't found where the UID history list gets
stored. For OL2007, maybe it puts that list in the file that you
mention. I'm starting to suspect the UID history is stored in the .pst
file.

Diane Poremsky [MVP]

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May 30, 2008, 2:28:05 PM5/30/08
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Why would you think this is about 2007 when the OP clearly stated he uses
2000?

> I move my Outlook 2000 info from one computer to another by copying the

Brian said it was stored in the registry in 2000. It's not., its in the RHC
file. It doesn't store all the message id's ever downloaded, just the
pointer for the last one downloaded.

I believe Outlook 2000 was the last yr they used the file. Now it's a hidden
Mailbox manager message in the pst.


--
Diane Poremsky [MVP - Outlook]
Author, Teach Yourself Outlook 2003 in 24 Hours
Need Help with Common Tasks? http://www.outlook-tips.net/beginner/
Outlook 2007: http://www.slipstick.com/outlook/ol2007/

Outlook Tips: http://www.outlook-tips.net/


Outlook & Exchange Solutions Center: http://www.slipstick.com
Subscribe to Exchange Messaging Outlook newsletter:
EMO-NEWSLETTER-S...@PEACH.EASE.LSOFT.COM

"VanguardLH" <V...@nguard.LH> wrote in message
news:V42dneymYdAFp93V...@comcast.com...

VanguardLH

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May 30, 2008, 4:19:52 PM5/30/08
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"Diane Poremsky [MVP]" wrote in
<news:4A4B4256-00DD-4E27...@microsoft.com>:

> Why would you think this is about 2007 when the OP clearly stated he uses
> 2000?

Because Brian mentioned OL2007. I didn't know from your reply whether
you were addressing OL2000 or OL2007.

> Brian said it was stored in the registry in 2000. It's not., its in the RHC
> file.

Okay, so it is just for OL2000 that the .rhc file gets used.

> It doesn't store all the message id's ever downloaded, just the
> pointer for the last one downloaded.

I guess that makes sense since presumably the UID always increases with
each subsequenct e-mail that is received.

> I believe Outlook 2000 was the last yr they used the file. Now it's a hidden
> Mailbox manager message in the pst.

Okay, thanks for that info.

Roger

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May 31, 2008, 11:13:01 AM5/31/08
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Thank you both for a very interesting discussion. I just copied my
outlook.pst file and took it to a computer that had not been used for
several months. I did send and receive and it only pulled down the messages
that were not in the outlook.pst file that I had brought from the other
machine.

I think the reason that this process fails sometimes may have something to
do with the hash value. I believe that the hash values must be in the
outlook.pst file since that is all I take and it usually works. If it fails
it wants to pop all the messages on the server, meaning that none of the
hash values match. My suspicion is that outlook must create the hash values
for the messages stored on the server each time you connect and then compare
them with the value in the outlook.pst file. The question is what does
Outlook use to create the hash value? For some reason, it must create
different hash values on the machine with the copied pst file, but only
sometimes.

Roger

"VanguardLH" <V...@nguard.LH> wrote in message

news:2badnTJ8Yvj5_N3V...@comcast.com...

VanguardLH

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May 31, 2008, 6:49:16 PM5/31/08
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"Roger" wrote in <news:e3fFbDzw...@TK2MSFTNGP05.phx.gbl>:

> Thank you both for a very interesting discussion. I just copied my
> outlook.pst file and took it to a computer that had not been used for
> several months. I did send and receive and it only pulled down the messages
> that were not in the outlook.pst file that I had brought from the other
> machine.
>
> I think the reason that this process fails sometimes may have something to
> do with the hash value. I believe that the hash values must be in the
> outlook.pst file since that is all I take and it usually works. If it fails
> it wants to pop all the messages on the server, meaning that none of the
> hash values match. My suspicion is that outlook must create the hash values
> for the messages stored on the server each time you connect and then compare
> them with the value in the outlook.pst file. The question is what does
> Outlook use to create the hash value? For some reason, it must create
> different hash values on the machine with the copied pst file, but only
> sometimes.

There is no hash or CRC value assigned to a message. The UID is
assigned to a message by the mail server. During the lifetime of an
e-mail account, the UID is to be unique for every distinct message that
is in that mailbox. So by knowing the account and UID, the message is
uniquely identified. There may be something to what Diane mentioned of
the GUID of the host also getting included in the .pst file.

Remember that Outlook can also be configured to behave like many other
e-mail clients in only downloading the headers of a message. That means
the body is not retrieved until later (you mark it and then later
download the marked messages). Well, without the body there would be
nothing to hash up to create a unique value for that message yet Outlook
will know which message to download when you mark it because of the UID
for that message that it got before.

Have you yet tried disabling the e-mail scanning feature of your
anti-virus software to ensure that it is not interferring with the
reception of your e-mails as it interrogates them?

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