I've just entered into this position for a school district. They've never had a real network guy before. Currently their email solution is using a local ISP to provide their email.
Their email is IPswitch. I do not have any control over the email system, only thing I can do is set mailbox size, change passwords, and create users.
We currently have around 250 mailboxes that we would need with possible growth in the future.
Would the Open Source edition of Zimbra be enough for my district. We would want the capability to share calendars. Have a desktop client.
I'd also be looking at archiving (mailarchiva)