Well, using IMAP I seem to be stuck - no new emails are coming in to the email client, so I can't attempt my test that I described earlier in this thread.

Also, the dates of all the emails downloaded so far are incorrect. The dates are the set to the date/time that the mail was downloaded, not when the mail was sent, so I have mails from 2011 that are dated yesterday.

I love the simple UI of OM, but due to some of these limitations I unfortunately must move on to another client.

Aha! The server (yahoo) is configured as POP. I have recreated the account using IMAP and will follow-up here if I can get it working. Thanks for the info!

Here's the settings dialog: http://screencast.com/t/im4Q7wg6ES8

The only relevant setting appears to be, "Mark messages as read if already downloaded" which is unchecked in my settings.

I just sent an email to my yahoo account from my work account. As soon as Opera downloaded it (it is still unread in my Opera inbox) it is marked as read in Yahoo's web interface.

When Opera Mail downloads messages from the server, it marks them as read on the server.

If I am running Opera at home, and I am not home, Opera will download messages and mark them as read on the server. Then when I check my mail from my phone or tablet, it appears there are no new messages (since they've all been marked as read when Opera downloaded them).

Is there any way to mark them as read on the server only after I read them in Opera mail?