Upgrading from Exchange 2010 to 2013: Mailbox considerations

There are a few key points to be aware of when upgrading from Exchange 2010 to 2013:

- You can only have 50 mailbox databases per Mailbox server (oposed to 100 in Exchange 2010)
- Exchange 2013 has a mailbox size limitation of 100GB

In order to give you an overview of the users use with Exchange (like average message size, average sent/recieved email per day), you can use a tool called Exchange Server Profile Analyzer.