I have several email addresses and several devices. I have IMAP set up for every account except for my Live mail account. I went out of my way to set up IMAP everywhere because of the fact that once I read an email on one device, it will get shown as read on all the others. I can also file emails and it will get updated everywhere.
So, the only hold out has Live Mail. I noticed that iOS now updates the read status of Live emails, so I thought that Live Mail must have added IMAP, but when I searched the web I could not find the settings. So, I tried the next best thing, I spied on the web traffic.
I installed Wireshark on my computer and configured the computer to be a wireless hotspot. I the configured the iPod to use the hotspot I just created. This way I could see all of the traffic to and from the iPod. To my surprise, when I looked at the traffic, it just looked like normal https web traffic. As a sanity check, I checked the email on one of my IMAP accounts, and as expected, I could see the IMAP traffic.
So it appears that Live Mail still does not use IMAP. Instead, it looks like There must be some https based protocol for interfacing to the Live Mail servers, and it appears that Apple has implemented this on iOS. So, as a result, I am put of luck when it comes to configuring Postbox to use IMAP on the computer.