·You import mail from Outlook into Outlook Express, but you removed Outlook from your computer before you tried to import the mail into Outlook Express.
·You configure Outlook Express to be the default Simple Messaging application programming interface (MAPI) client.
·You import or export mail from Outlook Express, and you do not have Outlook installed on your computer.
To resolve this issue, try one of the following methods, as appropriate for your situation.
Method 1: If you want to use a special program you can use Outlook Express Fix Toolbox
Method 2: Change your MAPI Settings
Configure Outlook Express to not be the default Simple MAPI client before you import the mail items. To do this, follow these steps:
1.Restart your computer, and then start Outlook Express.
to open theInternet Properties
tab, click an e-mail application other than Outlook Express in theE-mail
, and then clickOK
again to close theOptions
6.Exit Outlook Express, and then restart Outlook Express.
You can now import or export messages.