Intermittent failure to send outgoing mail

[Warren Post]

On one installation of Opera 11.50, 11.52, and 11.60, messages sometimes
remain indefinitely in the outbox and are not sent. This happens on only
one installation (a Portable Apps version on a USB stick). I also had/have
the same versions of Opera installed in the usual manner on a Linux box,
which does not have this problem.

I am unable to reproduce the problem at will; perhaps 30% of the messages
I attempt to send suffer this problem. Doing any of the following
sometimes causes the message to be sent, but not reliably:

* Double clicking on the message in the outbox to open it for editing,
and pressing the "send" button in the editing window
* Adding another message to the outgoing mail queue
* Copying the message's text into a new message, deleting the original
message from the outgoing queue, and adding the new copy to the outgoing
mail queue.

What never works is pressing the "Send Queued" button or its keybinding
Ctrl-Shift-K.

Opera is configured to send messages immediately upon adding them to the
outgoing mail queue. It is set to use TLS and not use port 25 to avoid ISP
port blocking.

What might I try to identify and fix the cause of this problem?

--
Warren Post
http://my.opera.com/wpost/

[Warren Post]

On Fri, 23 Dec 2011 09:35:11 -0600, Warren Post <inv...@invalid.invalid>
wrote:

> On one installation of Opera 11.50, 11.52, and 11.60, messages sometimes

> remain indefinitely in the outbox and are not sent...

Answering myself here, but for the sake of anyone else with the same
problem, it turned out to have been a simple mail server configuration
issue. Logging for outgoing mail per:

http://www.opera.com/browser/tutorials/mail/advanced/#outgoing

...indicated that my SMTP server did not support authentication. Setting
it to None resolved the issue.

--
Warren Post · New Media Copán
http://my.opera.com/wpost/