MSG viewer


 * iTunes: https://itunes.apple.com/nl/app/msg-viewer-for-outlook/id973213640?mt=12


 * In the free version you can convert one mail from MSG to EML.
 * In the pro version (17,99 euro per user) you have no limitations.


 * When the whole company uses Macs you will only store mails in EML format, then you don't need the MSG viewer anymore.