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Microsoft Windows Server 2013
Microsoft Exchange Server 2013. The Standard Edition is limited to 5 databases mounted per server. A mounted database is a database in use. A mounted database can be an active mailbox database mounted for use by clients or a passive mailbox database mounted during restore for log replay and replication. Although it is possible to create multiple databases of the previously indicated limits, it is possible to mount the maximum number specified above. The recovery database counts against this limit.
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