Today, I spent time troubleshooting Outlook Express, Microsoft's standard email application on Windows, which should not be confused with Outlook, Microsoft's more elaborate email client that can come package with MS Office.
A good place to start is reading should begin with Microsoft's Article on Outlook Express File Corruption.
In our case, we were able to get everything working by going offline, compacting the inbox and deleted items folders, and finally moving saved messages outside of the default Outlook Express folders.
If you are not as fortunate, you might take a look at some of the software tools listed below for repairing and recovering lost email with Outlook Express.
- DBXtract - Extracts messages from corrupt dbx files -- Slow, limited and may not get all the files.
- DBExpress - Extracts messages from corrupt dbx files -- Fast, accurate, and versatile. Can extract from entire disks, even if formatted
Even though I did not have to use these tools, they might come in handy in the future.