Rated 5 out of 5 stars

I know of no other way of reading Outlook emails with attachments using Thunderbird. This is so fundamental that it should be incorporated into Thunderbird. My thanks to Aron for this add on.

This review is for a previous version of the add-on (1.2.12). 

A new version has been pending approval for a few days. If you want to get it before mozilla approves it then click the link that says "see version history" or use this link (remove spaces if it wraps)
https://addons.mozilla.org/en-US/thunderbird/addon/lookout/versions/