Hi,So I am looking to purchase exchange 2007, do I have to purchase a CAL for each mailbox holder/user or do is a CAL for a simultaneous connection?For instance, would I need 100 total CALS for 100 mailboxes or I would only need 20 CALS for 20 people viewing their mail at the same time and if the 21st person went on they wouldn't be able to access it?How many CALS would I need for server 2008 to run exchange?Sorry if this has been posted before but I am having a heck of a time with this.Thanks

A CAL is required for each user or device (depending on the license) accessing the server You may find a local Microsoft reseller for consult Please check the Next Steps section in the How to Buy Exchange Server 2007