If you have backup of Outlook Express data, then use guide below, if not, then you may take a look at additional helpful articles/topics about getting rid of .dbx corruption

https://social.msdn.microsoft.com/Fo...ssengerconnect
http://bt.custhelp.com/app/answers/d...ox%2Foutbox%3F
https://www.openfiletool.com/dbxopen.html DBX Open File Tool – this solution provided for complicated .dbx corruptions, and only for them

Follow the instructions below:
1. Shut down Outlook Express
2. Click [Start]
3. Select Find
4. Select Files or Folders
5. Enter the name of the corrupt folder. For example, inbox.dbx
6. Click [Search]
7. When search has found the folder, right-click on it and select rename
8. Call it inbox.old (where inbox is the original folder name)

When you restart Outlook Express, a new folder will be created. You will need to repeat the above steps for each folder that is corrupted. The folders used by Outlook Express are called:
• inbox.dbx
• outbox.dbx
• sent*items.dbx
• deleted*items.dbx
• drafts.dbx