Thunderbird locking-up while downloading messages from an IMAP

Is this from a 1.5 upgrade or feisty > gutsy upgrade? what version of ubuntu, thunderbird do you have?
Please if it is an upgrade try using a new profile see if it helps. As for the title you choose to use, it is incorrect as you seem to be the only one with this issue since you filed the bug not commented on one of the choices you were given to report the bug, I will make it more descriptive.
Deveolpment on Tbird is moving along upstream. Please tell me where you are getting these ideas as ther eis no substance to any of them.

I have observed this with both a feisty->gutsy upgrade and fresh install of gutsy beta. I am currently running with a completely fresh install of gutsy beta with updates applied as they come through.

My information comes from two sources.

1) The reason given for the creation of a new organisation to be created to further development of thunderbird and the fact that present releases of thunderbird are produced solely by the Mozilla QA Team as, and when, they have time available.

2) The recent departure of Scott McGregor and David Bienvenu, both well-known thunderbird core developers, from the Mozilla Corporation. These are key individuals and thunderbird development will suffer as a result of their departure.

I don't make unfounded statements and if you believe that thunderbird-2.0.0.x is stable enough for gutsy release then I look forward to being proved correct once the bug reports do start to come in on this subject.

Ok lets start with your bug, have you tried using a new profile? alot of problems after upgrade are caused by profile corruption.
The info you recieved is correct however, there hasnt been any stop in thunderbird devel and they are still pushing releases shortly after firefox releases, Tbitrd 2.0 was delayed due to alot of show stopping (blocker) bugs. Thunderbird for as far back as i can remember has had issues with IMAP, This is the first bug of its type that i have seen,

If you have problems or a bug with thunderbird does not mean its not ready for use. We can not ship 1.5 in gutsy atleast if maybe 3 months ago you reported this bug than maybe, We will help you fix your bug but i believe this discussion on tbird devel needs to be moved off bug reports.

OK we'll stop development talk here but remember, you asked.

I am using a new profile. This is a fresh install of Gutsy Beta, not an upgrade.

The lock-up is a real problem. I have been working around the problem by setting thunderbird to *not* download messages at startup but as soon as a new message arrives it locks-up again. This I expect could be a real problem for users regardless of the fact I may be the first to report it.

Thunderbird-1.5 never exhibited this problem. In fact I've never had any issues with IMAP under thunderbird-1.x.

I'm also seeing IMAP issues with thunderbird after a dist-upgrade from feisty.

I've taken a look at the dovecot IMAP server running on Centos 4 and there doesn't appear to be many connections coming through from the desktops running Thunderbird.

Thunderbird is very busy doing something judging by the load on the box, but connection to the process with strace produces a lot of the following

EAGAIN (Resource temporarily unavailable)

Any ideas on what to do next to debug this?

Mine is not locking up, but is indefinitely popping up error messages saying that the IMAP server is not available (attached screenshot). On a small number of cases it actually fetches mail from this account, and works for the other accounts, but is consistently failing to find any messages from this one. The settings for their server, and instructions for Thunderbird, are at http://8help.osu.edu/2148.html and the IT staff suggested that I set the cached connections to zero, but every time I open Thunderbird, it defaults the cached connections to 5.

Is this symptom still reproducible in 8.10 RC or later?

Updated tag to imap. Please update info as requested so we can better help you.

I can reliably reproduce this problem. I believe it's a connection timeout somewhere in the IMAP message download. It only happens when I'm using a slow connection (less than around 100kb), and then any new mail over about 10k will cause Thunderbird to hang. The network monitor shows that all network activity stops after a short period.

This is a major problem for me as it prevents me from using Thunderbird while I'm connected using mobile broadband in less than perfect signal areas.

I've attached strace output. Thunderbird started downloading the first new email and after about 5 seconds the progress bar stopped moving, after another 10 seconds Tbird stopped responding completely. ^C on the strace hung after detaching 2 threads. Had to force-quit tbird.

I should have added that I'm running thunderbird 2.0.0.19, but every release of thunderbird seems to suffer from poor handling of IMAP connections over slowish links. Works fine on a decent connection.

Can someone please use 2.0.0.21 and test since noone has anything newer than 2.0.0.21

IMAP can be an issue in Thunderbird for some people, I have only had 1 problem out of 8IMAP servers in thunderbird bt that was just the inout box not being right.

I'm now running 2.0.0.21 and the behaviour is no better than with earlier releases.
Using a decent DSL connection I have no problems with IMAP at all, but on mobile broadband running anything less than about 1Mb/s accessing my mailboxes takes seemingly forever and usually fails with no errors. The cursor continues to show busy but all network activity ceases, new mail is not downloaded and clicking on an existing mail fails to display it. The only solution at this point is to exit Thunderbird and restart. Effectively I can't access my email except when on a very fast network connection.

Note this only affects IMAP. Pop mail handling is fine even on very slow links.

what imap server are you running? you might need to tweak the max concurrent connections for your account settings -> YOURACCOUNT -> Server Settings -> Advanced ...

try to lower them in case your server doesnt allow 5 (or whatever is configured there)

Can you please do what Alexander wrote. Thank you!

Closing because of no response from the reporters.