Try this,
Get all .msg files from the source folder using the “For Each File in Folder” activity. Read each .msg file using the “Read Outlook Mail Message” activity or a third-party package like Aspose.Email. Save the mail as an .eml file using the “Save Mail Message” activity, specifying the destination folder. Extract attachments by iterating through MailMessage.Attachments using a “For Each” loop. Save each attachment to the target folder using the “Save Attachment” activity. Ensure all necessary folders exist before execution.