Turn on suggestions
Auto-suggest helps you quickly narrow down your search results by suggesting possible matches as you type.
Showing results for
Duplicate UIDLs bug?
Topic Options
- Subscribe to RSS Feed
- Mark Topic as New
- Mark Topic as Read
- Float this Topic for Current User
- Bookmark
- Subscribe
- Printer Friendly Page
- Plusnet Community
- :
- Forum
- :
- Help with my Plusnet services
- :
- Broadband
- :
- Re: Duplicate UIDLs bug?
Duplicate UIDLs bug?
28-01-2008 3:43 AM
- Mark as New
- Bookmark
- Subscribe
- Subscribe to RSS Feed
- Highlight
- Report to Moderator
Two emailers I use fail to download several messages queued in each of my mailboxes. I mean they know there are, say, 200 msgs in a mailbox but only download headers and bodies for, say, 150. The rest of the messages are invisible (and these figures are not exaggerated). The developer of one of the mailers investigated the problem and claims PN's server has a bug and issues duplicate UIDLs which confuses mailers if they download messages from multiple PN mailboxes. This explains why PN's webmail and mail2web don't have this problem -- they look at one mailbox at a time. The developer's mailer doesn't have this problem either if it is set up to look at a single PN mailbox. The two mailers have been working reliably with PN's server for ages. This only started happening a few days ago -- or that's when I noticed anyway. It sounds like a bug and the developer even sent me a debugging version of his mailer demonstrating the problem. Can someone please investigate this.
Michael
Michael
Message 1 of 7
(1,635 Views)
6 REPLIES 6
Re: Duplicate UIDLs bug?
28-01-2008 8:56 AM
- Mark as New
- Bookmark
- Subscribe
- Subscribe to RSS Feed
- Highlight
- Report to Moderator
Michael,
What mail client is this happening in?
I use Thunderbird and it's set to poll multiple PN mailboxes using IMAP and I've never noticed this problem. Nor have I ever come across similar reports of the same. our mail collection servers use Courier AFAIK.
I'll pose the question to our Net-Ops guys to see what their opinions are and get back to you.
What mail client is this happening in?
I use Thunderbird and it's set to poll multiple PN mailboxes using IMAP and I've never noticed this problem. Nor have I ever come across similar reports of the same. our mail collection servers use Courier AFAIK.
I'll pose the question to our Net-Ops guys to see what their opinions are and get back to you.
Bob Pullen
Plusnet Product Team
If I've been helpful then please give thanks ⤵
Message 2 of 7
(703 Views)
Re: Duplicate UIDLs bug?
28-01-2008 9:01 AM
- Mark as New
- Bookmark
- Subscribe
- Subscribe to RSS Feed
- Highlight
- Report to Moderator
Can you post the offending emails headers with duplicate UIDLs so the PN developers have something to go on?
Its not something I have seen and I download emails from many mailboxes using Outlook Express.
Its not something I have seen and I download emails from many mailboxes using Outlook Express.
Message 3 of 7
(703 Views)
Re: Duplicate UIDLs bug?
28-01-2008 9:04 AM
- Mark as New
- Bookmark
- Subscribe
- Subscribe to RSS Feed
- Highlight
- Report to Moderator
i had this happen once last week, i use standard down load on outlook express, i now have thunderbird with imap, on the offending e-mails all the items in the headers were identical, unfortunately i have now deleted it.
Message 4 of 7
(703 Views)
Re: Duplicate UIDLs bug?
28-01-2008 9:06 AM
- Mark as New
- Bookmark
- Subscribe
- Subscribe to RSS Feed
- Highlight
- Report to Moderator
Interestingly, the POP3 RFC has the following to say about UIDLs (emphasis mine)
UIDL [msg]
Arguments:
a message-number (optional), which, if present, may NOT
refer to a message marked as deleted
Restrictions:
may only be given in the TRANSACTION state.
Discussion:
If an argument was given and the POP3 server issues a positive
response with a line containing information for that message.
This line is called a "unique-id listing" for that message.
If no argument was given and the POP3 server issues a positive
response, then the response given is multi-line. After the
initial +OK, for each message in the maildrop, the POP3 server
responds with a line containing information for that message.
This line is called a "unique-id listing" for that message.
In order to simplify parsing, all POP3 servers are required to
use a certain format for unique-id listings. A unique-id
listing consists of the message-number of the message,
followed by a single space and the unique-id of the message.
No information follows the unique-id in the unique-id listing.
The unique-id of a message is an arbitrary server-determined
string, consisting of one to 70 characters in the range 0x21
to 0x7E, which uniquely identifies a message within a
maildrop and which persists across sessions. This
persistence is required even if a session ends without
entering the UPDATE state. The server should never reuse an
unique-id in a given maildrop, for as long as the entity
using the unique-id exists.
Note that messages marked as deleted are not listed.
While it is generally preferable for server implementations
to store arbitrarily assigned unique-ids in the maildrop,
this specification is intended to permit unique-ids to be
calculated as a hash of the message. Clients should be able
to handle a situation where two identical copies of a
message in a maildrop have the same unique-id.
So, while UIDLs should be considered unique within one particular delivery session or mailbox, there should be no guarantee that this is so and the retrieval software should be able to handle the case of a duplicate message within one session having identical UIDLs
Across sessions (and checking two mailboxes means two sessions) UIDLs should not be considered unique.
B.
UIDL [msg]
Arguments:
a message-number (optional), which, if present, may NOT
refer to a message marked as deleted
Restrictions:
may only be given in the TRANSACTION state.
Discussion:
If an argument was given and the POP3 server issues a positive
response with a line containing information for that message.
This line is called a "unique-id listing" for that message.
If no argument was given and the POP3 server issues a positive
response, then the response given is multi-line. After the
initial +OK, for each message in the maildrop, the POP3 server
responds with a line containing information for that message.
This line is called a "unique-id listing" for that message.
In order to simplify parsing, all POP3 servers are required to
use a certain format for unique-id listings. A unique-id
listing consists of the message-number of the message,
followed by a single space and the unique-id of the message.
No information follows the unique-id in the unique-id listing.
The unique-id of a message is an arbitrary server-determined
string, consisting of one to 70 characters in the range 0x21
to 0x7E, which uniquely identifies a message within a
maildrop and which persists across sessions. This
persistence is required even if a session ends without
entering the UPDATE state. The server should never reuse an
unique-id in a given maildrop, for as long as the entity
using the unique-id exists.
Note that messages marked as deleted are not listed.
While it is generally preferable for server implementations
to store arbitrarily assigned unique-ids in the maildrop,
this specification is intended to permit unique-ids to be
calculated as a hash of the message. Clients should be able
to handle a situation where two identical copies of a
message in a maildrop have the same unique-id.
So, while UIDLs should be considered unique within one particular delivery session or mailbox, there should be no guarantee that this is so and the retrieval software should be able to handle the case of a duplicate message within one session having identical UIDLs
Across sessions (and checking two mailboxes means two sessions) UIDLs should not be considered unique.
B.
Message 5 of 7
(703 Views)
Re: Duplicate UIDLs bug?
28-01-2008 9:21 AM
- Mark as New
- Bookmark
- Subscribe
- Subscribe to RSS Feed
- Highlight
- Report to Moderator
Similar in the IMAP RFC:
2.3.1.1. Unique Identifier (UID) Message Attribute
A 32-bit value assigned to each message, which when used with the
unique identifier validity value (see below) forms a 64-bit value
that is permanently guaranteed not to refer to any other message in
the mailbox. Unique identifiers are assigned in a strictly ascending
fashion in the mailbox; as each message is added to the mailbox it is
assigned a higher UID than the message(s) which were added
previously.
In this case they are guaranteed to be unique within the mailbox, but not cross-mailbox.
B.
2.3.1.1. Unique Identifier (UID) Message Attribute
A 32-bit value assigned to each message, which when used with the
unique identifier validity value (see below) forms a 64-bit value
that is permanently guaranteed not to refer to any other message in
the mailbox. Unique identifiers are assigned in a strictly ascending
fashion in the mailbox; as each message is added to the mailbox it is
assigned a higher UID than the message(s) which were added
previously.
In this case they are guaranteed to be unique within the mailbox, but not cross-mailbox.
B.
Message 6 of 7
(703 Views)
Re: Duplicate UIDLs bug?
28-01-2008 12:21 PM
- Mark as New
- Bookmark
- Subscribe
- Subscribe to RSS Feed
- Highlight
- Report to Moderator
I've had several instances of Outlook Express refusing to display emails. The message appears in the list but gets a strikeout as soon as I access it. After that OE won't touch it.
Message 7 of 7
(703 Views)
Topic Options
- Subscribe to RSS Feed
- Mark Topic as New
- Mark Topic as Read
- Float this Topic for Current User
- Bookmark
- Subscribe
- Printer Friendly Page