If you need help migrating old Outlook Express data (.dbx files) to a new client, search for “convert DBX to Thunderbird” – free tools exist for that purpose.
Outlook Express was an email client included with Windows XP, Windows 98, and Windows Vista. Microsoft officially discontinued it over a decade ago. It is not compatible with Windows 10 or Windows 11 in its original form, and Microsoft does not offer any official download for it. download outlook express for windows 11