I have two Exchange 2010 (v14.00.0639.021) mailbox servers that are in a DAG and are both running Windows 2008 R2 x64 Enterprise. Using PowerShell on my first mailbox server that has all 8 active databases, when I execute the "Add-MailboxdatabaseCopy" command (e.g. Add-MailboxDatabaseCopy –Identity db3 –MailboxServer LargeMbox2 –ActivationPreference 2 –SeedingPostponed) to add the 8 database copies to my second mailbox server, I get an error saying my second mailbox server “ has reached the maximum database limit of 5” when I try to add the 6th database copy. I thought the limit of 5 database copies per server was only for Windows Standard edition- and I have Windows Enterprise? Note that both of my mailbox servers only have that one mailbox role (no other Exchange roles on them). Note that I was able to add the 5 database copies and start seeding them as well (using the Update-MailboxDatabaseCopy command in PowerShell). I was trying to add the 6th database copy while the seeding was still happening.
Below is the actual error I got in Exchange PowerShell:
Server "LARGEMBOX2" has reached the maximum database limit of 5.
+ CategoryInfo : InvalidOperation: (db51:ADObjectId) [Add-MailboxDatabaseCopy], RcrExceedDbLimitException
+ FullyQualifiedErrorId : B84BF0A0,Microsoft.Exchange.Management.SystemConfigurationTasks.AddMailboxDatabaseCopy