Some experts will say that this isn’t really something that *I* learned the other day. Technically they’d be correct, but when you think about it we talk about Message Class in Exchange and Enterprise Vault all the time.. but what is it?
We see things like this:
This is a machine running Outlook 2010 with the Enterprise Vault Add-in installed, and we can see that this item has a different icon.. so that is part of it.
If we use the ‘Field Chooser’, and add the ‘Message Class’ attribute we see things like this:
The latter picture gives a clearer view of this field .. Message Class .. you can see a meeting request that my test user sent to a colleague.. you can see regular emails (IPM.Note) and you can see an archived item.
Essentially the Message Class of an item is just an indicator to the type of message that is contained in the object. Outlook, Enterprise Vault and other tools and utilities will often do different things based on the message class of an object, and of course different related fields are expected depending on the type of message (eg a meeting request is expected to have appointment times and so on.. where as an email [IPM.Note] isn’t expected to have that)