Bug 2038

Summary: messages fetching processess should be non-blocking and fully interruptable/restartable
Product: Claws Mail (GTK 2) Reporter: Jakub Fiser <mr>
Component: OtherAssignee: users
Status: NEW ---    
Severity: enhancement CC: mail, mail, mr, netuse, yac
Priority: P3    
Version: 3.7.3   
Hardware: PC   
OS: Linux   

Description Jakub Fiser 2009-11-05 13:14:59 UTC 
some network problems causes the application to hang when receiving messages from POP/IMAP/NNTP servers.

New messages (all IMAP, POP and NNTP) are fetched for each account separatedly, one account at a time and in foreground. This causes blocking of the whole application if an error occures in client network connection (namely wireless signal loss, resume from hibernation, or similar) or network problems of some account's servers.

The fetching process cannot be interrupted before connection is established with the POP/IMAP/NNTP server, nor it can be restarted (the Get Mail button shows as disabled). This causes the whole fetching proccess to hang until timeout, which often occurs in matter of minutes, rendering the whole application unusable until timeout. The only workaround except waiting is hard-killing the application, which can (and usually does) lead to data loss.

By rendering the whole application unusable I mean literally, it just hangs, nothing can be done, it does not seem to accept any user input.

How to replicate:

add a few accounts (recommended all IMAP, POP and NNTP), hit the Get Mail button and unplug network cable (do not put the interface down).
Comment 1 J 2009-11-09 20:25:10 UTC 
Hi.

1/ You can stop mail fetching anytime using Ctrl+Esc/ Or "Message" -> "Reception" -> "Stop reception" 

2/ There is an option that is enabled by default, that makes a window appear when receiving mail, which causes the software to be frozen until end of reception. Disabling it makes the reception take place in the background.

"Preferences" -> "Reception" -> "Window" -> "Display a window during reception"

(Translation from french are mine, actual text may differ).

I hope this addresses your problem.
Comment 2 Jakub Fiser 2009-11-14 02:19:04 UTC 
Hi J
Comment 3 J 2009-12-20 22:55:45 UTC 
Thinking of it, Ctrl+Esc may well be a personnal shortcut. I don't remember exactly. Anyway it means "Message" -> "Reception" -> "Cancel" on my local config. Yet, you seem to get something from it. Perhaps it's a default shortcut, then. Just wanted to point that out, in case it could be confusing for anyone.

I'm afraid I won't be of any help regarding your issue.
Comment 4 Julien Lavergne 2010-10-29 17:06:47 UTC 
At least, isn't possible to add a button to cancel the reception, near the progress bar where you see the number of messages proceding ? because it's not obvious to find how to cancel the tranfer when you first look at the GUI.
Comment 5 Oliver C. 2011-02-18 14:51:44 UTC 
I also have this problem on NNTP, with the 3.7.6 on Linux, and it's worse than described above.

1. Cancel is not available (never available for NNTP, I believe)
2. Claws Mail runs at 100% CPU (of one core)
3. The timeout does not work, there is no way out other than hard kill

I waited 10 minutes or more and still could do nothing (with timeout at 5 minutes).

This is a major problem for me, because in my setting, it happens reproducibly for certain groups. 

Since there is also no catchup function, the workaround of avoiding the problematic range and fetching only newer news is also not available. 

In fact that means that occasionally, I can't read a Usenet group for a while, until the "bad article" has fallen out of the fetch range.

- fetching should be non-blocking
- cancel should be available
- timeout should work, well, actually, if the connection is lost, the client side should close the connection too, automatically, as my Windows Newsreader (40tude Dialog) does
Comment 6 Marco 2011-02-25 09:36:31 UTC 
Same problem here. Interruption while fetching NNTP messages blocks the whole application. ctrl+esc does not help.

How to replicate: as Jakub Fiser explains (2009-11-05). It seems to be enough to add an NNTP account, since mail fetching can be cancelled.

I completely agree with Oliver C. in the points for a possible solution:

- fetching should be non-blocking
- cancel should be available
Comment 7 Marco 2011-04-07 10:23:29 UTC 
*** Bug 2198 has been marked as a duplicate of this bug. ***
Comment 8 Raphael Michel 2015-03-09 21:56:32 UTC 
Is there any chance this is getting fixed? To me and several other people I know this is the only really annoying thing about claws mail, because the interface is frozen for up to multiple minutes after every network reconnect (e.g. due to a suspend/wakeup cycle or a WiFi change).
A interrupt button would be absolutely sufficient.