tl;dr: How do I import Outlook Express messages? Background: I used Outlook Express until Microsoft killed it, and have used Outlook 2013 since. Now Microsoft has forced me to abandon that due to Oauth2 not being supported, so I am looking for a replacement. Thunderbird seems to be a recommended solution, but despite poking around in the community forums and help files, I am not finding straightforward answers to my questions on the current platform. (Side note: I have been using Firefox since it was Phoenix and then Firebird, and then Firefox, but never really used Thunderbird.) I have a lot of really old .dbx files from Outlook Express. I heard that it is possible to import these into Thunderbird, but can't find any way to do so. These are low priority as they are archives and I just want to view them now and then, so not a deal breaker, but is that possible? It seems like it might require installing quite an old version of Thunderbird to make this happen? I thought I had found an article about it quite some time ago, but I just read through all of the search results for "Outlook Express" and couldn't find anything about bringing the messages in.