Windows VISTA Mail is an extension of Microsoft Outlook Express and a much stable release with lot of security patches. Unlike Outlook Express the Windows Mail does not uses .dbx email archive, instead it stores each email inside the respective folder as .eml file. Therefore, for each email you will be having that many number of .eml files.
The situation where drive has been reinstalled there are chances that lot of data has been overwritten. The chances of recovery will depend on the amount of data left without being overwritten. The other problem would be to find the correct allocation information to reach file.
Disk Doctors Windows Data Recovery software would be the best chance to recover those lost emails, you have NTFS recovery component and also “File Tracer” component to perform file recovery search for selected file types based on there unique identifiers.
You should not save or write on this newly installed Windows VISTA drive, this drive must be connected as a slave to another drive and the evaluation version of the software must be installed on the healthier partition.
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