Before you can export in Outlook Express, you have to install Outlook (full version) on that computer, then go into Outlook (full version) and set it as the default mail handler. Then you can go back to Express and export your mail. Copy that export file to disk and you can use it on another computer that has Outlook (full version). If you want to import back into Express, you have to first import into Outlook (full version) then export again - at least this has been the only way I've found around it! Lot of hoops, but par for the course with Microsoft.