We have a relatively new Exchange 2013 install. For some reason, despite only having one database (verified by running get-database command), I have 12 HealthMailbox accounts. From what I've read, there should only be 2 per database. I've tried wiping them all out and recreating, but they all come back. Any ideas why there are so many?

Is there just a single copy of this database?

As far as I know, just the one copy. It's not running on any other servers or anything. And there are only about 20 users, so it's not exactly a huge database either.

Hi five25,

Thank you for your question.

You are right. There are two health mailboxes that are created for a single mailbox database, one for mailboxes, and one for Public Folders (if deployed). 

However, When we install Exchange 2013, it automatically creates several HealthMailbox<guid> objects in Active Directory used by the managed availability service.  Exchange 2013 managed availability uses these HealthMailbox<guid> objects to send emails through Exchange to verify mail flow every 5 minutes, so we will have 12 health mailbox account though we just have only a database.               

If there are any questions regarding this issue, please be free to let me know. 

Best Regard,

Jim