The Bulk Importer provides a fast and easy way to import legacy emails.

It can import emails that have been filed to SharePoint or Windows folders with tools like Ideagen's Mail Manager and OnePlaceMail, MessageSave, Newforma, and many other systems. You can also import via a simple spreadsheet.

It's very easy to use so we have provided this 7 min video to get you started: Bulk Importer Tutorial

Automating the creation of an import XLSX file

If you have emails saved to a Windows file system and need to generate an XLSX file from it, this Powershell script can be helpful as it will create a CSV file listing all the folders that have emails, which you can then easily save as an XLSX and then edit: CreateCSV Powershell script