Are you using an IMAP Server from Ipswitch, Inc.? Do you want to migrate the mailboxes from IMAP Server to Outlook Live?  Before you begin the migration, consider the following issue. Files in the Inbox folder in IMAP Server will be migrated. However, any existing subfolders and subfolder content will not be migrated. This issue occurs because of the way in which results are retrieved by IMAP Server in response to the LIST command. 

To work around this issue, flatten the folder hierarchy in IMAP Server.