Error with Entourage 2008 Database migration to Microsoft Outlook Express 2011

Hello
Microsoft Outlook Express 2011 gave me this error message. I just think Microsoft should just keep to what they can do best. This happened only now that I was moving from Entourage 2008.
It took me like a whole day to do this. I had more than 2500 mails and about 2100 appointments.
The outlook express did not like the Entourage database. The image below shows the error.
Can anyone tell me what to do?
Thank you very much.

Microsoft Outlook must be closed because an error occurred. Any unsaved work may be lost.
